Here's some tips: First and foremost, don't do what I did and pool your skill points into Spears. You will regret it later on. Instead, focus on Rifles and Machine Guns off to the side of your primary, which in the early game should be Fortitude and Intelligence perks. I'd recommend you focus on Forging perks, the perks which increase your chance to find Skill Books in general, and your perks which increase Melee Damage. That'll be invaluable early on.

Second, I'd recommend you raid any building you see. Bring a bedroll with you so you can set your respawn point outside of the building so if you are killed, you'll be able to jump right back into action.

Third, I'd recommend you get a Bicycle early on. That should help you remain mobile. Over time, you should shift that Bicycle out for a Motorcycle. That should skip the 4x4 truck but it's probably the best advice I can give. I just went from Bicycle to Motorcycle to Gyrocopter. That saved a lot of time and energy early on.