I'm going to invest at 18, what do you think?

Hi everyone, I told myself that I would wait until I reached the age of majority to invest, that is to say next January, and I think that is a good thing. So here I have saved 5000€ to start but I don't really know what to invest in, I found some ideas but I need external advice I thought about bitcoin, the S&P 500, the stoxx 600 (or 50 I don't know yet) and gold too then I have an additional question on which application to invest knowing that I live in France. Have a nice day everyone!