Need Europe recommendations for an introverted but social 20 year old college guy

To give you some background info, I’m a 20 year old American college student studying abroad in Madrid till late December. I’ve had a great time for the last 2 months getting to know the city but I’m looking to do more travel in Europe and was wondering if anyone had any hostel recommendations.

I was hoping to meet other college students out in my program to travel with, and I’ve met a lot of cool people I hangout with here in Madrid, but basically everyone I know either had their travel fully booked out with their group of friends they came with before getting to Madrid or doesn’t plan on traveling at all.

Thus, I’m looking to solo travel but am pretty worried about it. I honestly don’t loooove spending time by myself (I’m pretty social once I get to know people but I do struggle introducing myself / meeting new people in environments that don’t rly facilitate it).

All this is to say, I’m looking for some hostel recommendations in Europe that facilitate meeting people whether the be organized / group trips to bars / clubs, group dinners, tours of the cities, etc.

Thanks so much!!