TORS mean Throttle Override System. This is also referred to as TSS ( Throttle Safety System ). This monitors where your throttle is at, compared to your carburetor. In the event that your throttle gets stuck wide open, it will cut back your sleds power. There should be a wire than you can unhook to bypass that system.

is there a diagram that shows which wire it is

Depends on the state you like in. Most states do not have a licenses for a snowmobile. 12 years old is consider by most to be old enough to drive in a supervised environment. Snowmobile safety classes are offered by some states as well most starting at the age of 12.
It depends on what state you live in. At age 12 you can get classes.