There are no potions in Unchained X. You heal by attacking enemies so they drop health orbs, opening green treasure chests, or using medals who have healing properties for their special attacks.
What you might be thinking of is that if you traverse the map and walk over sparkles on the ground you will collect what is known as Materials. Some of these may look like potions (glass bottles of water, swamp water, dew, etc) but they aren't the same. These materials are used to upgrade your Keyblades.