Where Is my Dad In FALLOUT 3???

Yeah. You need to go through the super mutants. I recommend that you do the survival guide quest chain in megaton before you go there. It makes it easy to level. Also once you unlock the perk, "Here and Now," get it right away. You will gain a whole level or more depending on what level you are when you use it. (I got it at like 17 cuz I am stupid.) It shouldn't be all that hard to find him. You just need to follow your comp.