How to achieve a prop trading internship as an undergrad student?

I have just finished my freshman year of college as a math major. I don't go to an HYPSM college and I wonder how difficult it is to get an interview when I apply to firms like (IMC, Optiver, Akuna, etc) during my junior year. I also wonder how much does the college you go to weigh in during the final interview process. I hear some people say that becoming a quant trader is mostly meritocratic and acing the interview is what matters the most. If that's the case, does that mean I should worry the most about preparing for the interview. Should I take a calculus based probability class and study extremely hard the months before I get an interview or does that not cut it. Do I need to have a stellar resume like extensive research experience, internships at big tech companies, win math/cs competitions? If I can't expect to get into any of these top firms, are there lower tier firms that are less selective?