Your plan to transfer from UMD to a UC is not a good one. Going from a large east coast state flagship university to a large west coast state flagship university is probably not going to change your student experience very much. The detour through a community college (which will probably not be as academically strong as UMD) makes a bad plan worse. You could give up a spot at a very good university and have no guarantee of acceptance somewhere better for you.
My advice would be to spend time working on adapting to where you are. Every university has a freshman support plan with different kinds of resources you can take advantage of. Make sure you are using everything you can. If it doesn’t work out by the end of the third semester, take a good hard look at what you need, visit campuses, and transfer from UMD to a school that would meet you needs. (I’m worried that you haven’t really thought through your needs since your current plan is a school like UMD, just in a different location.)
Sometimes students don’t understand how to make the transition to college – this video explains some of the things that students should know when they feel lost –
https://youtu.be/MftaGHKt3V0