To "copy" android screen to TV, lots of TV these days come with a mirroring feature, consult TV manual.
To use phone as an Internet hotspot, u need a feature called tethering, will use cellular data, not easy subject, ask Google.
If you have an old analog TV then you need some kind of box/stick either connecting directly to TV or your converter box IF it has a video input port and normally this box/sticks directly get its things from your home network.