Do you have a gas cap for XL12 part #A69500A?

Standard plug gap for a chainsaw 0.5mm

My old Homelight XL12 used 30:1 , but most modern two stroke engines use 40:1. Probably run in either but need some carb adjustment. Start with choke full on and throttle wide open.

that must be a old one my books dont go back that far , if the case was lt /gold id say 80's if case was orange then it early 90s

Here are free UT10490 Parts Diagrams you can print:

https://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/green-machine/homelite/chain-saws/xl12-chain-saw-ut-10490

Homelite XL12 parts manuals

Yes you do! The ratio is 50:1 fuel to oil. Be sure to use a modern synthetic saw oil available at home centers, hardware stores, and saw dealers. Be sure to use fresh fuel and mix the two in it's own container. Be sure to shake the container thoroughly each time just before refueling to prevent oil starvation in the engine. Don't make up more than one gallon at a time unless sawing is your business. Hope this helps!

The engine is running hot. A build up of chain lube/saw dust/dirt is likely blocking cooling air to the cylinder cooling fins (and gas line and carb) causing the fuel to boil (vapor lock)
Compressed air, played around openings in the shroud, will sometimes remove enough of the obstruction to help and is worth a try. Best solution is to split and remove the case/cover, after which, the engine and shroud can be throughly cleaned. Be sure to stuff a clean rag in the carburater throat to keep debris out.

The preset is to turn them all the way in (Don't tighten them hard or you will damage the needle) and then back each out 1 1/2 turns. This will get you started. You can then run it at full throttle and turn the high speed jet in untill you hear a change in the RPM. Then turn it out untill you hear the same. Find the happy medium.