Hey girl! Kudos on joining the gym and starting your journey to a healthy lifestyle! There is no routine or set of workouts or number of reps and sets you need to do. You do what your goals for your body are. It all depends on what you want to work on. You should never go to the gym without a plan. If you walk in there without knowing what you are going to do, you will just end of wandering around and wasting time. Start off with a nice warm up like a few minutes on the treadmill to get your heart rate and adrenaline going. If you aren’t sure how to use a machine, there are usually little instructional pictures or don’t be afraid to ask a worker, that’s what they are there for. Work on different muscle groups a day.