The game starts you out at like combat level 8, just do all the tutorial stuff and follow the dotted paths. Once you get to an area where you're supposed to kill goblins you should hit level ten. If you don't, you don't really need to farm as you have to immediately go to the other side of the camp to then kill wolves.
If you somehow still haven't reached combat level 10, then just keep going and you'll get another quest from a guy out in the woods where you have to kill many tree creatures.
If you see that your combat level is 10 or higher in the upper-left corner but still don't have this, then Xbox achievement servers or the game might be broken.