I applied for Biology major. I got accepted to CSU Long Beach and got waitlisted to both UCB and UCD. Assuming that I opt in and get accepted to both UC’s, I am not sure about where to go. I plan to go to medical school and I know that UCB is really competitive, so I’m scared that I won’t get a high-enough GPA to get into a medical school. As opposed to that, I am considering to go to a community college for two years and transfer to either UCSD or UCLA. I’m thinking that this will save me money and my GPA will also won’t suffer. But at the same time, I’m wondering if I’m not gonna waste the opportunity at Berkeley, if I do that. Please give me your opinions! It will be greatly appreciated 
thank you in advance!
I would say that UCD is a great option to get good GPA and be in a school that provides you enough opportunities/great education! I’m not sure about CSULB though. Berkeley is definitely very competitive, so your worry is true (based on what I hear).
You should treat your waitlists as rejections and focus on CSULB at this point.
If you get off the waitlist for either UCD or UCB, then you will need to make a decision but based on past experiences that it is highly unlikely you will admitted from both waitlists.
Have you visited the campuses? UCD is very different than UCB. UCB can be ultra competitive especially for Pre-Med Majors, so you could probably get a better GPA at UCD but that really depends upon you.
Are costs significantly different? You want to spend the least amount on your Undergrad since Medical school is very expensive.
Visit each campus and see which you prefer. Remember a happy student is a successful student.
Since its just a wait-list, I wouldn’t waste too much energy on what ifs. Consider them NO and move on with your life. Lock up some housing at LB before it vanishes. If you get off one or both waitlists, you can evaluate the situation then.