Get it started on starter fluid. As the engine starts to die, keep pipping the starter fluid to keep it chugging. Little short squirts. Try this about 10 times. Engine should briefly run up each time. Might be enough to fire the engine up.
I suspect gas.
You can also pull plug, heat it carefully with torch, reinsert and start up with fluid.
Alternatively, you can blast the ever loving daylights out of the carb with carb cleaner.