If you take CC classes while you are a high school student, it is considered “dual enrollment” and you can still enter as a freshman to a four year college (not sure how that works if you intend to do the CC route and transfer to a UC). Given your rocky start in HS, you might be well advised to go that route. That said, I believe that some schools don’t consider freshman grades, so you might be okay. How are your stats (e.g., GPA, standardized tests?)
As for how schools consider classes taken at CCs, it’s up to your HS whether dual enrollment grades figure into your GPA or not and/or whether or not they will fulfill your graduation requirements. You need to talk to your GC.