So go through files and just delete the valheim folder with everything in it then re install in steam?

After the uninstall you just want to delete Valheim

steamapps - common - Valheim

There is some valheim stuff in appdata but that is your world and character save data. You don't probably want to delete that.

Uninstall game
Manually go to the install folder and delete it totally. This is the only way to remove mods or corrupted files. An uninstall will not remove files it did not think the game put in.
Reinstall "clean" copy of game

Test function
Add updated mods <I don't mod so can't help you there>