So yeah as above, assuming it was going before and just left, I'd make an attempt to drain the fuel or at least syhon as much out with one of those squeeze syphon things, then have a look in the tank with a torch. Add fresh gas.
Check air filter hasn't disintegrated.
Check to see if it turns over. If it starts, yay. Maybe a spray of engine start spray.
If it doesn't start or just won't run right when off choke you will need to strip carb as old petrol can be a mess. Plenty of info on web, try YouTube.
Once going get it warm then change oil.
Brake fluid and new tyres/inner tubes for safety as they will be from last century.
Sorry to hear about your father, hopefully this will be therapeutic.
Seek help if you have to sort out tax. Ird are infuriating. Just trying to clear estate stuff myself for final tax returns.
Don't you look at my accountant.
He's the only one I've got.
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