If it’s been sitting for a while I would get the carbs cleaned out. I had a similar issue with mine after it sat for 2 years. The pilot jets needed to be replaced/carbs cleaned out/new plugs/new fully charged battery and fresh fuel is what it took. It now runs perfectly!
Also, it should fire in less than 10 seconds. If not, you could burn up your starter if you keep the switch in to long.