I prefer and recommend the very simple boglehead approach to investing. Simple 3 fund portfolio, focused on long term growth.
Lots of forums on their website, but basic idea is split your money into a healthy mix of total market, international, and some bonds. Focus on tax advantaged retirement accounts. Invest early and often.
https://www.bogleheads.org/wiki/Bogleheads%C2%AE_investment_philosophy
Specific guidance for Italy: https://www.bogleheads.org/wiki/Investing_from_Italy