Go to a community college that offers all of the pre-recs you’ll need for your major. Keep your GPA up, hopefully in the 4.7+ range (not sure for your major, just in general for UCLA) and try so so so hard to get A’s in all of your pre-rec classes. Once you have that down, get involved. My CCC (SMC) has a stem program that I would definitely look into for the CCC you attend. Try and get involved in school by holding leadership positions and volunteering consistently starting now. Just remember that GPA/finishing pre-recs are THE most important parts. Also follow and finish IGETC, the core classes for everyone. Try to finish any pre-recs the fall before you transfer if possible as well. Some people will tell you it doesn’t matter, but I’ve heard from multiple counselors that it does so I’d rather be safe than sorry. Good luck!!