im right hand dominant but my left bicep is noticeably fuller on the inside than my right. Im currently on week one of a gvt routine. What exercise is best to bring up the inside of my right bicep

Something other than incline db curls which doesent seem to help
How supanated ur wrist is depends on which part of ur bicep gets worked out most.
most people's are uneven to some degree. If you new to working out they will get closer together over time. i was the same way, but they are still a little uneven
Just make sure you do the same weight on both sides and concentrate on form. It'll even out eventually. I've lifted for years, but my left arm is still stronger than my right for whatever reason, but no noticeable size difference.