I want to know, I basically go to the gym five days a week to lose weight and gain muscle, but I basically don't eat dinner. Is this important?

It depends on how much you exercise. If you consume a lot, you need to replenish energy. If you spend a little, you can skip dinner.

Take your time to lose weight and gain muscle, and don't rush for success. Otherwise it will affect health.

I do 100 pull-ups every day. 150 flexion and extension. 1000 sit-ups (all stages). Help yourself to dinner, not much. The effect is not bad.