Hello Tillie and welcome to the group...
I think you are wanting to switch from an electric start to a pull start. Right??
If that is the case you need to determine what make the engine is, most likely a Briggs or Tucumpsie...
You should be able to locate the recoil mechanism that mounts on top of the flywheel.
Check with mower repair shops for used parts that you need, they usually have a lot of junk engines setting around to cannibalize good parts from...
The swap your contemplating is very easy, most folks go the other way pull start to electric, your swap will be very economical as well... :smile:KennyV