Honestly, it's impossible to even guess what you might make during your 1L or 2L summer at this point. The range is very broad, and your options will largely be based on grades and connections.
That said, there are some general rules which are applicable to just about everyone. First, many summer internships (especially nowadays) pay little or nothing. There are so many well qualified law students competing for experience in big cities like L.A that employers don't have to offer high pay (or any pay) to entice good applicants. Most government internships will pay nothing, or maybe a small stipend.
I was fortunate enough to work at a very good, highly regarded government office during law school. Even though the internship was unpaid we had something like a few hundred applicants for three or four spots.
Big firms can pay well, but the competition to land those positions is intense. It helps that you're at UCLA, which has a great local reputation and strong alumni network. Nonetheless, the big firms will be inundated with applicants from UCLA, USC, Stanford and Berkeley, not to mention Harvard, Yale, etc.
I don't know if biglaw firms are still doing this, but a few years ago I knew 2Ls who were getting paid the same monthly salary as first year associates for the summer. I think they were making about $20,000-$25,000 total for the summer (10K per month, or so). Again, I would caution that these positions are highly sought after, and they will expect stellar grades to even be considered.
Obviously, small and midsized firms re going to pay a lot less.