Okay, from your character sheet, go to the tab above that says Town Place.
When you get there, there will be three tabs below it. Click the one that says
Temple.
You can restore your health there, or you could also use potions which I
believe can be found in the magic shop.
Jay's right. ^^
The temple will heal your HP (and MP) outside of battle, while potions will do it during a battle.
You can also check this post from the Newcomers Help Center for more info on healing.
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