That depends in the model and what transaxle it had. Typically it will be by the shifter that you grab to put it into reverse.
The safety switch to start the motor on a Ranchking riding mower is located in the ignition. If the clutch needs to be depressed several times before the mower will start, there might be a problem with the adjustment of the clutch.
This is usually caused by a faulty seat safety switch.
On most MTD riders it is right by the seat hinge on the right side as you sit on the mower.
Most riding mowers have three or four safety switches. One for the seat, one for the clutch/brake pedal and one for the deck height lever. If the mower has a deck engaging lever there is one for that too.
My Huskee mower will not mow in reverse due to a switch that kills the engine if the blades are engaged. This is very inconvenient. I removed the switch and it now mows in reverse. Do this at your own risk. I am the only person who uses my mower and it will be reinstituted when I sell the mower.
Generally the ignition switch activates headlights on a riding mower and the start position only send current to the starter solenoid. If you turn the key and the engine cranks over than the lack of spark is going to be something else. If it is a riding mower you will have several safety switches to prevent start up under unsafe conditions.
The engine kill switch is under the seat.
A riding mower is safe to use if one follows the safety guidelines. Most of these guidelines are common knowledge. If one is safe, and doesn't mess around on a riding mower, there isn't any risk to using one.
find the switch, cut the wires, strip and connect with a spring type wire nut or crimp type solderless connector
The seat safety switch is not working properly correctly. If the safety does not sense that there is anyone on the seat then it will shut down the mower. This keeps the mower from running over someone if they would happen to fall off while mowing. Or if the safety is working you may have bad bearings on your deck and that will also stall your motor, or something jammed in the blades.
It is not strictly legal for me to answer that.
Normally you will find three safety switches on a Huskee riding mower. There is one for the clutch/brake pedal. There is another one for the deck lever and the main one that causes problems under the seat.