Can you use Apple Watch series 2 with a prepaid iPhone it said you can't with series 3?

Can you use Apple Watch series 2 with a prepaid iPhone it said you can't with series 3?

The Apple Watch doesn't know (or doesn't matter anyway) if it is paired with a prepaid iPhone. The only thing that makes a phone considered prepaid to begin with is the SIM in it, not the actual phone.

Don't know what "it" is, but you could pair any Apple Watch with any compatible iPhone model no problem, no matter if it is being used as a prepaid phone or postpaid phone.

Yes, as long as the phone itself supports the Apple Watch (which it should).

The Apple Watch 3 includes a cellular connection, which means (as far as a cell company is concerned) you need a plan for it and a pre-paid one won't work. If you don't activate the SIM in the watch it should still work.

Yes

Yes

Both series 2 and series 3 watches will pair and work with any iPhone, regardless of how you pay your carrier. What will not work with prepaid phones are Series 3 CELLULAR. These have eSIMs in them, and to function independent of the phone they regular a paid line access fee (in the US all 4 major carriers charge 10 bucks a month for this). That requires a postpaid service, no (at least US) carrier offers this on prepaid. However, a series 3 Cellular will still work perfectly fine over bluetooth connection to a prepaid phon (but you've effectively wasted $100 on functionality you can't use, just get the Series 3 BT version).