Without knowing anything about you, I would advice any 18 year old to get an advanced degree. Without getting into the economic situation of Italy, which I know something about but even more I know there is a lot I do not know, you are inside the EU and can move freely. Not far away from you people are risking their lives and literally drowning by the thousands just to be able to clean toilets. When you are depressed, this idea doesn't help. But it is something to try to be aware of anyway.

You say you are not capable to do any job. I do not know if that is true, and I do not know what exactly you mean with this. Does this mean you cannot clean toilets or pick fruits from plantations, like many immigrant workers?

I don't know if you have a physical handicap, lack of motivation, difficult situation at home, no financial resources, mental illness, whatnot. But you are 18 in the biggest free market in the world. Yes, Italy's economy hasn't grown ever since it entered the EU. But other EU economies have. And so far, Italy hasn't collapsed yet, even under Berlusconi. And if it does, you can get out.

I would look at getting a technical degree, so either science or engineering. Or a technical degree in business or economics. Or a law degree in specific fields that are unpopular with students, and popular with employers (I think usual fiscal/tax law degrees),

You have to find something where your talent, your interests and job opportunities come together. This is hard. But you didn't phrase your question in a way that you are aware that this is your challenge, and that you are struggling at it.

Just remember that society is changing. The world has been globalized, causing big economic growth but leaving behind lower educated and rural/traditional areas. They are now 'rebelling'. But it soon will get worse. Technology will be replacing jobs more and more and at some point, getting near full employment will be fundamentally impossible. It is good that we won't have to work as much, while the economy is getting more productive. But there is no solution as to how these people without jobs, people that are not needed, will get money. So as an 18 year old, your biggest aim should be that you will never be one of those people that enters a workforce that will be completely replaced by algorithms/robots, leaving you in a position where you have exactly 0 to offer the economy.

Of course that doesn't mean you will be leading a satisfied happy life, but it should be a start.