2014 Mercedes C250 won't start

2014 Mercedes C250 with 65k miles suddenly won't start. I put the key in
ignition and it will allow me to completely turn the key but then there is
nothing. I do hear a humming sound coming from the dash, but the windows
won't roll down, the car is stuck in park and the brake lights won't turn on.

I have checked the battery using a multimeter and battery is fine. Because
the brake lights wouldn't turn on I thought the brake light switch needed to be
replaced, but the car still won't t start. I have checked the fob and that seems
to be working fine, but when I hit the panic button and put the key in the
ignition the alarm does not stop.

If anyone can point me in the right direction, please help. Unfortunately I
bought the car used 4 months ago and don't have a spare key.