I have a ford yt 16h Kohler lawn mower it won't start why?

It turns over real good it work 3 month ago cuz I saw my friend mowe with it. It was given to me by the new neighbor cuz the old on died. So what could be wrong with it?

Check the condition of the seat switch. Check the condition of the PTO safety switch. Check for spark: spark plug, plug wire, magneto production. Just because it's spinning doesn't mean the ignition is working.

Check to see if it has gas.

Check to make certain you have spark. Remove the plug wire from the plug and use a screwdriver to hold it against the engine. If you have spark, try spraying a shot of starting fluid in the mouth of the carb. If you have spark, and the ether doesn, t cause the engine to try to start, you may have a timing problem. If the ether causes the engine to try to fire, you have a carb or fuel problem. If you have no spark, you probably need a coil.

I found out the problem it was the carb I cleaned it and drained the old gas out put it back together and she started right up first turn of the key.