Do some research on scooter engines Reesy, sounds like you're just discovering the world of transport and engines so I'd make sure you're clued up before you go getting yourself a scooter.
Scooters are two stroke engines, that means they require petrol AND two stroke oil to be flowing through the cylinders. The petrol is what burns to make the explosion and propel you forward and the oil keeps everything lubricated and helps prevent wear and tear through friction.
As has been said, there is normally a seperate tank for the two stroke oil, so the engine mixes it for you. If this is the case, all you need to do is make sure your oil tank is filled up (check every time you fill up the bike to be sure).
If you buy an older one, you'll need to add the two stroke oil directly in to your petrol tank. They'll give you a dilution ratio which (making up a number here) means say you need a fifth of the bottle of oil to every full tank of fuel.
You can use any fuel in your scooter, as they use carbs and are not injection (therefore not controlled by a computer or "ECU") you won't notice any gains from running it on something like Shell V-power as they are set up to run on 85octane fuel (normal unleaded).
Hope this clears up your queries, and if you want to know more, just ask
