Creating an app and need help with adding a specific function

I have created an app for gym tracking ( I have different screens for every day of the week). Each screen has an add button at the bottom of the screen. I want to make it so the add button being tapped makes an add-exercise window appear, then this window will contain name of the exercise, target muscle group, sets and reps. After i fill the required fields and press again add from the popped window, i want it to disappear and add the individual exercise to the day. Here is a prototype