How many internships did you apply to?

Depends on how much time you have. While of course, the more places you apply to the higher the chance of getting an interview, you don't want to sacrifice quality for quantity. For example, a sloppy resume and cover letter riddled with typos sent to 50 places will yield fewer results than a polished resume and amazing cover letter sent to 10 companies with which you have networked a good amount. This seems kind of obvious but you'd be surprised what some people think.

Very case specific. I only applied to one, others applied to 20+.

Around 80 online resume drops. I'm from a total non-target state school. Of the 80 Only 2 became interviews. 1 ended in an offer. Aside from those, I networked hard with 9ish MMs and balance sheet banks and 3 became interviews, one offer. Took the offer at the place I didn't network at. Go figure.

There's some wisdom in here somewhere. Never give up or something. But, it definitely depends. I spent a lot of time sending those. And, the places that responded without serious networking made sense (professor was super high up before he retired at one and the other loved local schools). I also spent a lot (probably more) time networking with BB/EB guys and at banks that were obvious cultural misfits.

IDK. Where you end up tends to make sense. But, applying is 100% the easiest part of the process and networking is just about the only thing you can control . So, if you don't step up here and canvas the street, you probably don't deserve a seat.

Probably 20 and barely no responses and I'm not even half way through my freshman year

For Summer 2019, 4 applications, 3 offers. I lucked out and had a great sophomore internship so I could be a little more targeted in my networking/applications.