I would use a raspberry pi 4 but your need get a good way powering it up as it need a power supple with 3.1 amps
I am using a raspberry pi 3 as it easer to get power to the pi but its up to you which one to go with .
just think of how you going to get right amps to the pi so you only have to use one cable TV Monitor laptop screen with driver board.
when i did my first magic mirror i solder the wire inside an 3amp power plug that fitted into the back of my mirror you could do that with a raspberry pi 4 plug a spur from the main incoming with to your monitor TV etc.
anyone have a better way of powering up the pi 4 to tv