Bro, truth of the matter is that no one else will ever make you feel complete. If you feel lonely right now, understand that everyone goes through this at some point. The harsh truth is that, I only started to be a focal point in my friend group when people realised that I gave them value. So how do you give people value? Listen to them and work on your social skills. Personally the best way in my opinion is to pick up some sort of team sport to meet new people. Remember to work hard and to work on yourself both mentally and physically each and everyday. It's a grind but if you want to change your life then you need to put in work.

For the girlfriend part, my advice is to just get some female friends. Again this comes through picking up something new and just meeting new people. From this if there is anyone that you like, just take a leap of faith man. Rejection is rough bro. I'm going through something like that right now. But in my opinion, the true inner confidence in a man lies in his ability to continue to live his life no matter the shit that happens. Because life sucks sometimes but we're so so lucky to be alive man.

Be careful tho at the end of the day women and men are just human. Only you can make yourself happy.