1) turn in the mixture screw in until it just bottoms out. Be easy and don't over tighten. Turn it out 1 and 1/2 turns. The engine should start and idle at this setting. Once it warms up you can fine tune it.
Why does the choke not work? Will the cable move freely when not connected to the choke? You'll need full choke to get started.
PB Blaster or similar can unstick the problem.
You may have flooded the engine. Reset the carb and let it sit overnight. You can also check the plugs to see if they're gas soaked.
Good luck
