That’s a simple question, but the answer could go on for days.
Think about pre-flop action. If you’re under the gun on a 9 handed table, you have 8 people that act behind you. Generally, you want to have a much tighter range UTG because if you raise light there’s a higher chance you get called or raised. That’s why you should be very cautious of UTG raisers as they should have premium ranges.
As you move closer to the button, especially if it’s folded to the button, your range is wider. You can open with a lot more hands here since you only have a few players left to act and you have last action throughout the hand. You can open hands like 87 suited or KJ offsuit here, when you wouldn’t do that in earlier position.
Post-flop, you just get more information if you’re in position. If the flop comes all spades, and you don’t have a spade, you’re probably checking if you’re first to act. But if you’re last to act you can bluff at the pot easier since your opponent did not, but bluffing first to act here can lead to a lot more trouble.
Basically, position gives you more information, which makes hands easier to play and give you more power over other players. If you have a more specific question, that would help out, and I’m sure other players will have some additional info to add.