Healing so far has been done through food but I am gathering loads of stuff that I thought I could eat for health but I can't. With that said what do I do to heal? Is there a trainer for me to learn to make potions? Can I become an alchemist besides being a fighter? Came back to the game after not having played it for three months and am lost but really I don't think time is the issue. I need instruction. This is why I miss the old days of gaming where we would actually get printed manuals.

Yes, you can learn alchemy skills (called 'Medicine'), as well as other 'Professions' independent of your character's build. You can find tomes in the starting open area where you learn Survival, one in a basement for Medicine, and I've yet to find one for Crafting just yet. I've just started this game, and very early on while following the main quest, you will go into the basement of a burned down building, where you will find a medicine crafting table and a tome that teaches you the ability to make potions and gather plants. You can level up Medicine by crafting potions.
There is also the Survival profession that allows you to catch fish and cook food, which you can use to heal.