Do you have a computer on your outboard,if so borrow a laptop,buy the software and cable and diagnose problems and log maintance.
Its spark or fuel, replace all on motor fuel filters, there are very small fuel filters on fuel injectors if you have them.
See if you have suction on the fuel line before you put it in small gas can. If you have carbs, is there gas in the bowls?
Checking for spark is fast and easy with a spark checker, I make sure there's spark first before I look for any fuel problems.
Put some gas in a clear glass jar, se if it goes in the motor.