What exercise and diet could i do within 20 days ?

I want to Get my legs and abdominals in check by July 19 . I am 5'3 135 lbs and 20 y.o female .. what are good workouts I can do with 2 hours at the gym the next 20 days .. please help I've been working out since march with no real weight loss and I'm getting so desperate I'm thinking about skipping meals again but I want to give this one more chance