19 year old college guy – Europe summer?

I’m a 19 year old and my school starts in mid September. I want to spend a month in Europe solo traveling, probably from mid July to mid August. I don’t know where but it seems like it would be an awesome experience.

I want to spend about 4k for the trip, don’t know if that’s too much/little.

My current places I might want to visit are: Amsterdam, Barcelona, Lisbon/south of Portugal , Ibiza, Rome, Berlin.

Any tips on how I should organize my trip, what places I should add/remove and how to budget? I’m also vegetarian if that impacts good things.

I’m looking to really meet cool people, party, experience the culture and hopefully grow as a person. Any tips and recommendations are much appreciated!

Edit: I’m also a POC with dark-ish skin if that impacts things culturally and whatnot

19 year old college guy – Europe summer?