A healthy party is a party of content adventures in Baldur's Gate 3, but keeping them 100% is a challenge. A member of your party may have injured themselves while making a far jump or triggering a trap that caused the injury. Dumb mistakes like this are common, but just because someone is injured doesn't mean you need to remove health potions. There are cheaper methods of healing your party members.
The first thing to do to heal a member of your party is to check if there is food in their inventory. Food is an inexpensive way to regain some health points, especially at a lower level. You could gain four or six health points after eating an apple, and fully cooked meals are an effective way to gain even more.
If you don't have food, check to see if everyone is injured. When an entire group is not at 100% and you can use a break, a short rest is a good idea. You can only do this once per day between long rests, so those are also valuable, but your last and final option should be to use health potions and healing spells.
Most of the healing potions you'll find in Baldur's Gate 3 come from merchants, looting random boxes, old backpacks, corpses, or as rewards for completing tasks for NPCs you meet. They are instrumental, and you mainly want to reserve them for use during combat. Drinking one only costs as a bonus action, leaving your character able to perform their move and action, spell, or attack. All potions are limited in quantity.
The same goes for healing spells. A caster's healing spell usually costs them one spell slot, which they usually only recover after a long rest. It's a full night's rest, and your group may not be able to return to their camp to rest.
There are plenty of alternatives for treating members of your group. Just because the food doesn't say in the description that it will heal your character doesn't mean that it won't. But make sure it's not dangerous. A fungus that you find on the ground by someone who has only lived in the city could turn out to be poisonous. However, a trained ranger or someone with a background nature can easily pick the best berries and wildlife that are safe for everyone to eat.