Will eating at night make me gain weight?
Yes, eating after 7 pm will be digested slower. This happens because your metabolism slows down. You also will not burn as many calories because you will be less active.
7pm should be your last meal
Right before you go to bed? Yes. This is because your body doesn't have enough time to digest food. Maybe a tiny snack a few hours before bed is okay.
Generally at night we are less active, so anything that we eat will have less of a chance to be burned off via exercise. So it can lead to one gaining weight.
Eating carbs at night will. Since you go to sleep so you don't get any time to burn it off.