Gas coming out the wrong hole

I think I would start with cleaning the carb, it could be a problem with the float needle valve not closing causing a constant flow of fuel. Hopefully it's something that simple. Other possible issues I could think of is it jumped time or a valve problem. How's it running? Did this start after sitting a long time?

It's a motorcycle article but explains what your issue could be.

Why Does My Motorcycle Carburetor Spit Out Gas? | Motorcycle Habit