If your gut feeling is "Yeah, I've always wanted to ride a 70's french boomer bike". "It's different". "I'm saving it from the landfill", or something like that, then it will be obvious that learning about and working on it is going to be a fun life lesson. If all you want is something with two wheels and practicality, and you have a bike coop near you, I would see if you could strike up trade in talks with them. Maybe they would give you a price break on a newer and more standard bike, if you donated the Gitane. Just saying.