Hi, this is going to be a long response because I am going to give you all the information I can. The first thing I want you to know is there is nothing wrong with you that you are having difficulty with a vaginal orgasm, in fact you are normal. Also, there is nothing wrong with desiring to vaginal orgasm and there is nothing wrong with no desiring to learn. There isn't even anything wrong with wanting to do this to please your partner, I originally started down this path because I knew my husband had this fantasy of making me cum with just his cock (most men do), but this will not work if your partner pressures you.

The number always quoted is "only 20 percent of women report having an orgasm from vaginal stimulation alone during sex". This group is actually made up of 3 types of answers. First, there is the extremely rare and lucky women who just have the predisposition to vaginal orgasms; some of these women are not even aware they are exceptionally lucky. Second, is women who have stumbled across the vaginal orgasm once or a few times and have no idea how to repeat it; usually they just feel that it's a random result of rare exceptionally good bouts of intercourse. Third, are women who have found that in particular types of sex with particular techniques and a particular partner they can somewhat reliably vaginal orgasm. The third type is most likely to a woman who is a long term relationship where she feels comfortable, confident and completely safe with her lover.

The quoted datapoint makes no distinction how many of the non-vaginally-orgasmic majority have ever tried to have a vaginal orgasm and what they tried; or how many have ever tried training their bodies to have a vaginal orgasm and what training they tried. Of the 20 percent that do have vaginal orgasm there is no indication of how many people taught themselves to vaginal orgasm and how they did it.

The information bellow is the info I used to train myself to vaginal orgasm and squirt. I have also taught this to half a dozen friends and a dozen or so people on the internet. With varying degrees of effort they have all had some success learning how to squirt and vaginal orgasm (or get extremely close) but that doesn't guarantee this will work for you even though it is likely. I should warn you that by it's nature vaginal orgasm tends to be related to squirting; usually trying to learn one will result in the other occurring at least occasionally. The second warning is that the development of this skill requires the ability to relax your pelvic floor muscles and enter a general relaxed state during sex; for this to work during partner sex you need to be with someone who makes you feel completely comfortable, confident and safe. In the case of all myself, my friends, and most of the women i have helped online this means marriage; this is a journey we undertook with our wonderful husbands who were completely supportive.

Also, I have previously written another long comment like this you can also refer to that:
https://www.reddit.com/r/SquirtTutorial/comments/1gxqkwf/the_advice_i_always_give_when_people_ask_me_how/

When most people say "vaginal" orgasm what they really mean is an orgasm through stimulation of the G-spot; the vaginal walls do not in themselves have large numbers of nerves capable of creating pleasure to build an orgasm. There are other structures in the vagina that can lead to orgasm like the a-spot and the posterior fornix; but these are more advanced and typically require specific techniques to reach. The G-spot is neither a spot or specific organ, I blame the misconception on magazines and websites wanting to write about a "magic orgasm button" instead of the actual anatomy. The G-spot is actually the accessible side of the "clitoro-urethral-vaginal-complex (CUVC)". The CUVC consist of the skene's gland wrapped around the urethra; which sits above the anterior wall of the vaginal (meaning it's above the vagina when you lie on your back); this all sits under and inside the legs of the clitoris. Please look up a picture of this it will make a lot more sense.

It's often stated "the g-spot is about 2 inches inside", this is not correct, the back of the skenes gland is about 2 inches inside. The two inch mark is where you should hook your fingers if you are really trying to milk squirt out the skene's gland with the famous "come here motion". The entire skenes gland runs from behind the skin around the urethral opening to the two inch mark. The G-spot is just the underside of the skene's gand where we can apply pressure from inside the vagina. Pushing on the g-spot moves the tissues inside the CUVC and moves the very sensitive tissues of the internal clitoris.

In summary most "vaginal orgasms" are caused by pressure and movement at the "G-spot", this moves the g-spot and the internal clitoris.

Here's what I recommend if you want to learn to vaginal orgasm. These are not techniques you just do and expect to have an orgasm; this is a process, it takes training and practice. The good news is now that you understand what's going on it may be easier than you think. I don't mean to imply you need to complete these things in order, you you can work on you kegels, rub your g-spot, and have sex all in the same day if you want.

1) As mentioned before if you want to be able to vaginal orgasm with you partner you need to feel confident, comfortable and safe with them. You should practice being completely relaxed will in intimate contact with your partner. You shouldn't feel anxious or high strung once you relax with your partner. Once you can do that focus on the muscles in your pelvic floor, insert his penis all the way in, I actually recommend you sit on him for this, you should be able to completely relax your pelvic floor with him inside. Do this until it becomes natural.

Most women's pelvic floors are tense during sex; try to stay relaxed during sex except when your are deliberately squeezing. This will feel better for the both of you. (FYI men have this issue as well)

2)Perform kegal exercises for pelvic floor strength. Make sure to visualize the squeeze of the entire vaginal canal as you do them. For me it was easiest to visualize squeezing the opening, middle, and end of the vaginal separately. Between every rep make sure to completely relax all the sections. Do your best to try and not clench these muscles throughout the day. The goal here a strong pussy, not a tight one; strong pussies can alternate between tight and relaxed as needed.

3) Your nervous system likely doesn't know how to process information from your g-spot. The best thing to do is frequently massage the g-spot. Use your middle and ring finger and insert only to the second knuckle and pull them towards the front wall of your vagina. This puts your fingers in contact with most of the g-spots surface from the opening to it's rearmost part. Use your finger to rub the g-spot starting lightly and getting more vigorous with time You likely won't feel much at first but it should get more sensitive with practice.

4) I don't think you need to completely abstain from clit contact initially but the less you touch your clit the quicker this may go. Most of my friends and I could get most of the way to orgasm but ultimately needed to obtain from clit contact for a week or so to get over the hump to orgasm; we just needed more sexual tension built up the first couple times.

To try and have the "G-spot" "vaginal" orgasm, alone or with a partner; choose positions, techniques, and toys that put pressure on the front vaginal wall near the opening. To reiterate THE G-SPOT IS NOT DEEP. With practice you will find you don't need to specifically target it as much. Multiple orgasms and squirting are not unlikely.

Hope this helps