How do you get hit points in Kingdom Hearts?

Answer 1

Level up by bashing more Heartless (such as in the Coliseum) to eventually grow your HP gauge unless you're already Lv. 99.

To regain HP, defeat Heartless and pick up their HP orbs, stand on a save spot, use a healing item (Hi-Potion), or use magic (Cura). Or, you can wait until a teammate heals you with an item or magic.

If you have no MP but wish to use curing magic, use an MP-healing item (Elixir), equip a teammate with an MP-healing item, or equip the ability MP Gift to a teammate like Goofy. MP Gift sacrifices the user's 1 MP to give a teammate 3 MP. In this case, Goofy should probably have a few Ethers, so that you can have way more MP than your MP gauge can contain.