As I said: Do I have to have a TV for the Nintendo Switch?
No. You don't have to.
No you don't have to, I only play mobile, that's the advantage because it has its own screen, I don't give it back
No you don't have to. You can also use it as a handheld console without a TV.
No.
Either you use it as while holding it in your hand, but you can also connect it to a monitor (via HDMI)
No television is required for setup
No…
you can hang the normal switch on a TV or monitor in addition to "mobile" operation. The Switch Lite does not have this option