RC is a program within LSA. You can apply to get into the RC after you’re accepted to LSA.
LSA is the College of Literature, Science, and the Arts. That’s the division of University of Michigan you are in if you are majoring in English, biology, history, math, chemistry, French, anthropology, art history, etc.
RC is a living-learning community that some LSA students choose to be a part of. In addition to the academic requirements of LSA, the RC has an overlay of requirements. Also, the RC students all live together in East Quad freshman year and sometimes sophomore year as well.
Here’s more info about the RC:
https://lsa.umich.edu/rc/about-us.html
https://lsa.umich.edu/content/dam/rc-assets/rc-documents/RC%20Fact%20Sheet.pdf