Clemson or U South Carolina for premed?

which one would be better for a premed student and why?

They would both be the same. Premed is just a path and both of those schools will have quality bio, chem, ochem, and physics classes.

Go to the cheaper one.

Apply to both.
Both will be very competitive, with weed out classes.
Premed is just a set of courses and both universities will have those.
The key element is you - which one is a best fit for you.
But until you’ve been admitted to both, don’t count your chicken until they’ve hatched,
and apply to other colleges too.

Medical schools want to see some individuality among applicants these days. You’ll need a background in Math and life sciences of course, but in recent years many different kinds of undergraduate majors have been admitted to medical school. I think M2CK’s son was a ChE major.