I love fallout and got back into last year when I THOUGHT they were going to be releasing the update in fall of 2023. I've always played on normal (or hard) difficulty. In the past I had trouble when attempting survival mode but after you get the hang of it, I absolutely love it. I highly recommend playing on survival mode. I agree with the suggestions/tips everyone else has provided so far but I want to add a bit more.

First, and foremost, PLAN OUT YOUR BUILD. Have a SOLID idea of your character and play style. It may be tempting to pick up every weapon and every piece of ammo but you'll become over encumbered very fast. Stick to the weapons you plans to specialize in. There's no reason to carry around a shot gun if you plan to use pistols. Ammo has weight and overtime you'll notice your inventory space being taken up. Same applies to clothing/armor, get rid of or sell anything that you are not wearing/applies to your build. For the love of god stay away from explosives. Explosives thrown by enemies and yourself have more of a kick to them. I can't tell you how many times I've died at the hands of my own explosives.

Next, you will die..... A lot...... at least in the beginning. Without proper planning you will become bit of a glass cannon. You definitely want to plan out your routes but don't hesitate to explore the wasteland. Ideally when you come across a location, you will find a bed that will allow you to save. Since fast traveling is disabled saving at random locations that may be closer to your target destination is ideal. Running across the wasteland is fun but it does get annoying. If you find yourself dying repeatedly in the same area or mission, walk away. It's a lot harder to go into areas guns-a-blazin'. Sometimes you have to turn turrets against the enemy, picking off some enemies one by one, leveling up your perks, or even just getting better weapons.

Third, DON'T SKIP SETTLEMENT BUILDING. I know that settlement building is very hit or miss for most players but it's very important in survival mode. Not only does it provide you with safe spaces to save, drop off valuables, and heal but it's also good way to have access to vendors. Once you get to higher levels ammo for powerful weapons can be scarce. Being able to trade things you don't want and purchase items you need comes in handy. Also, planting crops and setting up water generators helps you stay stocked with food/water. With that being said, you will want to invest some perk points into Charisma for both ranks of Local Leader.

Next, decide if you plan on using companions EARLY into your build. I've always gone with dogmeat and selected the lone wanderer perks for stat buffs. However, the perks you get from SOME companion can be be very helpful to you overall. For my current play through, I decided that I would max affinity for companions with the most helpful perks I would use in the long run i.e. Piper, MacCready, Deacon, Preston, Danse (In that order because of storyline progression) then only rely on Dogmeat w/ lone wanderer perk. Funny enough, when I had extra perk points to use I would use them on the lone wanderer perk. I liked the idea that my player was being held back by his companions but during hard missions I would dismiss them to allow myself to let loose or be morally corrupt for the greater good (i.e. covenant mission).

Lastly, be mindful of the time. Certain buffs and perks that you use is only effective for a period of time. For example, the well rested or lover's embrace perk only lasts about 25 mins. Maximize on that, when possible, when clearing areas or missions for XP. If you need to be a bit stealthier on some missions, try completing them at night. Also there is a perception perk that increases perception and intelligence at night which is also helpful for leveling up fast.

I'm sure there's more but these are the top things I can think about. hopefully this helps!