I would go to the auto or hardware store and by carb cleaner. Remove the mixture screws if it has them and spray through all the jets. Don't use a screwdriver to reinstall them as you will wreck them and the motor will never run correctly. The carb will need to be adjusted when you get it running but it should be nice and clean.
Screw the adjustment screws in with your finger just until they bottom out, don't tighten. Then back out 2 turns.
Make sure all the gaskets are good, and don't forget to squirt carb cleaner through the float valve.
If you want a new carb or a rebuild kit, call these guys.
https://www.bills-place.net/