If it is a really big hole you might need a tractor plug.
Same stuff, just bigger
And use mower plugs not car ones
Most car ones have a heat activated glue and mower tyres never get hot enough for it to work so a week latter it is flat again.
Plugging the tire may seem cheesy but in most cases will outlast the lawnmower, And if the tire get unpluggable then pull the plugs and put a tube in it unless the tire is just coming apart and I mean separating.