My daughter (now 20) did something similar last summer: Prague, Berlin, Copenhagen, Malmö, Hamburg, Amsterdam, and Paris in a couple of weeks, IIRC.

She left with a friend, who headed home after a few days, so she ended up traveling solo for most of the trip. She stayed in hostels (bar in Paris) and ate basically only TooGoodToGo food [0] to save €. She made it home in one piece, with the biggest smile on her face.

[0] https://www.toogoodtogo.com/