How to delete on screen button that gets qu;ick access to various functions

I installed a button on my iphone 6s that when I press it I get quick access to various functions such as, Notifications, Device, Custom, Siri, Home, and Control Center in the first screen. By pressing Device it takes me to a second screen with more functions., On this screen if I press more, I get a new screen with more functions. As I previously mentioned I installed this button on my iphone 6s. Now I would like to delete the button and can not figure out how to delete it. Help would be greatly appreciated.