All I want to do is, when I have my shield on my left hand and flame spell on my right, I want to replace the flame spell with the healing one through the quick menu, but I can't do that, because the quick menu will assign the healing spell to my left hand and will replace my shield with it, leaving me healing in my left hand and flame in my right one. Is this impossible to do?

Anyone?

If your using an Xbox controller assign it by pushing the left trigger for your shield and your right trigger for your flame spell.

If you mean hotkeys on the pc, with spells, hitting the button once will put the spell in your left hand, if the spell's already in that hand, it add it to your right hand as well. So basically, hit the hotkey for your healing spell twice to equip it to both hands, then hit the hotkey for your sheild to reequip that to your left. It's a little clunky, but it works.