I can’t find a tutorial on how to repair a flat tire?

If replacement tires aren't available then there are alternative repairs to consider. Is there a tire valve to refill with air? A tire valve suggests flat fix from auto stores; can of flat fix, green slime, tire plug. No tire valve means its unrepairable unless thinking outside the box. One method is to refill the tire with foam, sold by the can with a plastic straw to fit into gaps for weatherproofing around windows, cracks, etc, against cold air infiltrating into a home. The foam is a liquid under pressure and expands several times to fill voids. One youtube video presents all methods of tire puncture repairs on lawn tractor tires; https://www.youtube.com/watch?v=k8IZjt2c.... Injecting foam is permanent. Acetone is the solvent for foam cleanup. Use disposable gloves as liquid foam is very sticky and messy.