That's an issue/problem right there, normally either LH or RH brake lever switch supply 12volt + power directly to both the brake lights and the "Safety Relay", wich connects the starter buttom to starter relay, allows bike to crank. You could have 2 bad brake switches
(bad/dirty internal contacts) or no power at switches from fuse box, you can disconnect wires at brake switches, check for 12v on one of the wires(switch on) , if no power, check dirty/poor wiring connectors, dirty or blown fuse, if you get 12v, install a jumper at either switch and try to crank." Make sure you apply brakes and/or do this on centerstand, for safety".
The fact that you hear the fuel pump priming, means both your sidestand and kill switch are operating normally.
General notes/PSA, fuses is the first thing to check, not always the issue, usually the result off shorts, broken wires, dirty connectors, bad grounds and/or fuse contacts, etc. " Never jump start or connect scooter/motorcycle battery to a running car/vehicle, you could cause $$$ damage "
IAC, this diagram may help.
