Would it be over training to do squats and deadlifts on the same day? If so what is a good exercises i can use on my squat day to beef up my lower back? Would partial deadlifts be good or something else?
My low back is wiped when I try t dead and squat on the same day. I train the low back with hamstrings on a different day.
Depends on your goals, your current level of expertise, your planned amount of sets, reps and weight(the volume), your recovery abilities, and what you do for the rest of the week.
Give us some more info and we might get a better picture.
SRS
Sure, you can do squats and deads on the same day. Train one hard, and take it easy on the other. Then switch it up the next week. I’ve done that with success.
As SRS said, give more information.