Just came into a working 122s from 1960. Drove it about six hours and now it's leaking a light green fluid from the radiator. I'm fairly new with cars so any help would be appreciated regarding where I can go from here.

Also sorry if in the wrong section, forum noob here.

 

You would be grouped into the "all other Volvos" forum. Sounds like you're loosing coolant, antifreeze. Check your hoses and hose connections. If the radiator is leaking you can use a local radiator shop to get it repaired. Around my town, most will get it done in under an hour and under $30.
Most radiator shops will remove and replace it for you at the going labor rate @70/hr
You can handle this one and you may reuse the coolant you drain out when you pull your radiator.
Very cool! You're gonna have fun.
Get a book for it.
Ed