(19F) In Europe with a little extra money, how do you actually start investing?

A few days ago I was at a bar with friends and a guy started talking to me about stocks. I honestly thought he was just hitting on me, so I didn't really pay attention, but he kept saying that now is a great time to buy because the market is going down?

The next day my friends brought it up again and said some of what he said actually made sense, which got me curious.

I'm 19, I live in Europe, and I have a little extra money from my last paycheck that I could try investing. Not a lot, just something small that I'm okay experimenting with.

But I have no idea where to start!!

Where do beginners usually start? What apps or platforms do people in Europe use? And is it actually a good idea to start when the market is going down?

Any advice is appreciated! :)