I was helping Vilkas go to the temple and on our way I made a pitstop at a dungeon.
Inside the dungeon he would get hit only once and be down on the floor with barely any health...

So, I'm curious if followers have levels and if so how to do you check it and get them leveled?

Generally I don't take a follower because they ruin my sneak attack, don't do anything useful or end up getting killed because they stand right in front of me.

If there is a similar question on here please direct me..I've searched but haven't been able to find anything useful as of yet.