In the "Workouts" screen, you will be able to see the weekly programmes that have been assigned to you on the top of the screen. If you want to do another workout, you can just scroll down and browse through the available workouts.
Once you are ready to begin your workout, just tap the first exercise to see a video demonstration of it, read the exercise instructions, and see how many sets and reps of it you have to perform. Tap the amount of reps you included in the set and the weight used if you wish to update it.
After completing all the exercises included in a workout, tap "Complete workout" at the bottom of the screen, insert the time that it took you to complete the workout, and tap "Complete Session" then you will be redirected to the "Workout Complete" screen where you can see the review of your workout, rate it and even share it.
If you want to see and manage past or future workouts, you can browse through your schedule by tapping the arrow icons left and right of the week that you are in.