If it won't turn over.
Starter not spinng?
Start spins but not engaging?
Starter engages but the engine won't rotate?
Need more info.
With the carb leaking, I would be leaning towards the floats stuck open with and electric fuel pump. Cylinders are full of gas. If it is a mechanical pump, that can not happen.
If it has an electric pump, I would pull the spark plugs before trying to crank it over. Then rotate the engine by hand on the crank bolt to empty the cylinders. Do not use the starter to crank it over, unless you have marshmallows ready to toast.