Help with schedule?

I’m an oncoming freshman at UCSD and will be starting in the fall quarter. I’ll be in Sixth College as a human bio major. The 4 year planning tool gave me the following schedule:
Chem 6a
Math 10a
BILD 4
CAT 1

Does this seem like a hectic schedule? I completed the IB Diploma, so I received a heavy workload in high school and developed study habits.

Admittedly, I didn’t really study anything over summer. What’s worse is that I only took a general chemistry class my sophomore year and not AP chem because the general chemistry teacher was the same as the AP chem teacher, and she didn’t teach anything. She took other teacher’s slides, made us copy them, then tested us on something else entirely, so I don’t know AP level chemistry for 6a… idk if I should do Chem 4. I heard it was ridiculously easy, like sig figs and such, but I want to be certain.
Also, I never took calculus. I did pre calculus my junior year and did IB math my senior year. There was a calculus unit where we learned derivatives and integrals, but that’s it. I don’t even think the derivatives and integrals were on a level as advanced as calc bc, so I’m worried over that too.
I can’t control CAT, so I’m stuck with that.
Regarding bio, I’ve heard it was easy to pass so long as I remain diligent in my studies because the catch with that class is that it’s time consuming and that if I were to fail it is because I didn’t do my work rather than the difficulty of the class itself.

Sorry if I am hard to understand. I typed this really quickly because I’m trying to figure this stuff out before enrollment comes around in like a week or so. Also, if anyone can recommend good/easy professors for any of the mentioned classes, please do so. If you have suggestions on the math and chemistry classes (for instance, insight on beginning with chem 4 vs chem 6a), that would also be much appreciated.

Thanks so much!