Remove Xfinity Rented Modem and use my own Netgear modem

I am currently renting a modem from Xfinity for internet, and I would like to remove the Xfinity modem and use my own. I purchased a Netgear Modem and attempted to set it up both through the Xfinity app and the Netgear app, but it failed every time and couldnt connect. It looks like I need to remove the Xfinity modem from my account first, but there is no way to do that in the Xfinity App. How would I go about setting up my own modem and removing the Xfinity modem?