Hi there. New to this but here goes. I have a Rheem RGMC-125A propane furnace that is 24 years old. Never any problems till this winter. Is has a constant pilot flame. We lit the pilot and it works properly. When we turn on the thermostat, it clicks but nothing turns on. The burners do not ignite and the blower doesn't kick on. Can anyone send me in the right direction. Thank you.

Did you turn the valve back to the on position if so your valve could be shot

Does your furnace have forced draft, and if so, is the blower running?