Take the spark plug out and pu a small amount of fuel ( I use carb cleaner ) down the hole replace the plug & crank
Engine fires = ignition timing is good & plugs working
Do the same down the carb throat
Engine fires a few times = valves are also working
That leaves fuel as the problem
Remove the solenoid in the carb & check that it retracts when the key is in the on position.
Let us know how it goes & don't forget to answer Rivets questions above at the same time .