Learn basic mechanical skills first. Then buy a project car or two. Once that's done, find a classic car that's very common in your country already, that way it'll be easier to find parts, advice and contacts. Beetles for example are pretty much universal no matter where you are in the world. Join an Owner's Club forum by the time you get your machine running, they'll help you keep it running. Then after you've got used to driving and maintaining your first restoration, try another of the same model. Then another. Gradually increase the level of degradation of the cars you find. Then if you feel proficient try a new car, something rarer.
Also, here's what you want to avoid as a beginner:
>Chassis damage
>Rust that has literally eaten away at the bodywork
>Pillar damage (a single cut through any of the six pillars reduces your car to immediate scrap)
>Interior damage outside of seats/belts and steering wheels (if the dashboard's been ruined/torched/hacked at with a machete just leave it)
Those four things don't necessarily make a restoration impossible, but they will add significant chunks of time and money to any project.