You can cast restoration spells to free parts of your body while in combat. That should help you with 1v2 scenarios. Though bare in mind that the game is still not balanced as new updates will include mechanics that affect combat. Game is still in prototyping phase so I am trying out different things and keeping the ones that look fun. That is the reason why balance is still not something that I work on right now.
You can level up by draining stats from a defeated NPC. To do that just go to bound NPC and interact with them by hitting 'E' to reach UI component that allows it. There are limits on how much you can drain and how many stat points are needed for a level up. I will eventually add a tutorial to the game that explains the intentions better but it is still too early for that.