This behavior depends on the accessory you put on your skin in minecraft person, example:
Guitar in the back: when you are in the inventory there will be an option with a music icon, that icon would let you choose the background music of the game.
Wings: with those wings you can do double jump since if I allowed you to fly it would not be fair.
Weapons: If you carry an iron axe on your back, when you enter a new or old world, no matter what, you will have that weapon.
Backpacks: if you put this in the inventory you will have extra space.
Snow shoes: with these shoes you will run faster in the snow when it is snowy snow.
Among other things, depending on what you choose in your avatar, not all things in the editor will have an effect on the game, but others will, but not all, and here is an idea of skillful clothing.
Rocket boots: these boots you could put in the editor and if you try it in the game it will let you fly for a period of time.
Idea By TheRedstone26