Help To Start a 440

Any tips or tricks to get a 440 motor running and stay running?

Would bad timing cause a no start ?

Air, fuel, spark.............I get it

I have fuel at the carb.............How can I test spark, by myself?

I was able to get the motor running for 5 seconds, it sounded good, then died

All it wants to do is crank...........novice looking for help

Thanks!