Can i connect 2 relays of the same specs and same coil voltage of 12 in series ie 86 of one relay to positive battery, it's 85 joined to 86 of the other relay and obviously the end 85 to ground??
Both relays need 12V to reliably operate the coil, in series they will only get 6V.
So, no this is not a good idea.
The best is to connect them in parallel and they will operate at the same time.