I had my tablet turned off because it would not come on but now it comes on . Can I use It with my wff with out turning it back on ?

I'm a customer the same as you are. That said, if you were referring to your wifi (not wff) then yes you can use any wifi compatible device as long as you remember any passwords to start it up and that it wasn't locked due to a security issue. Verizon reps can give you a definite answer though.

Yes you can

Use it if working.

Yes you can use your WiFi for service.