:welcome:
If that is the one with the plastic clip on float bowl, you just replace the bowl as all te jets are in there and it is not really servicable.
The engine manual is readily available for free on line google the engine numbers you posted and "service manual" .
The fuel filter will need replacing , this should be done every second seaon without thought along with the air filter.
Don't be intimidated by the age of your mower.
It will outlast anything built in the last 20 years.
I have customers qued up for old reliable robust mowers