I got a C in calculus 1 and an A in calculus 2. It says on the site that I must get a 3.0 or higher in these courses.
You didn’t say what your major is, but according to their website (https://www.admissions.uci.edu/apply/transfer/requirements.php), a lot of majors do require that you get a B or higher in Calculus 1 and 2. Since you said the website lists that you need to get a 3.0 or higher (B = 3.0), I would assume that you are applying for one of these majors. They are called requirements for a reason, so if you don’t meet the requirements, then you will (most likely) be rejected.
If it happens to instead be one of the majors that says you need a 3.0 average rather than a 3.0 for each of Calculus 1 and 2, then you would technically meet the requirement.
@uctransfer2020 is correct. It depends on wording. If each course needs to be a 3.0 it would seem you are out. However if it’s cumulative, the C and A make it a B (3.0).