Research for my story?

So I had a random idea about one of my characters in my story who got shot in his leg in Iraq. OK, so I basically know nothing about guns or being in war or anything like that. But if a soldier got shot in his leg, could it be bad enough to the point where he would have to be relieved and go home. Would he be able to be in a wheelchair for a few months and eventually be able to walk again? How long would all of this take before he could be able to walk or be on crutches?