Ok Love

Need some help. I want to cut the cord from uverse. I know I need to get 2 more firesticks for my other 2 TV's. I have internet from ATT. I plan on signing up for Youtube TV. What kind of internet do I need? I know I will be using far more data, so should I get unlimited from another company? Will I have to get a modem to carry the wireless connection to the second floor? Right now I have a uverse modem. I guess ATT will want their modem back. I plan on disconnecting from ATT this week but I want to be prepared for decisions I have to make when I talk to them. Thank you