This bill allows qualifying undocumented students to claim California residency, and therefore receive in-state tuition (WAY lower than out-of-state/international fees).
These are expansions of AB 540 so that it covers more undocumented youth.
This graphic from Immigrants Rising shows the currently qualifications for AB540 (including the AB 2000 + SB 68 updates). You can use their qualifying tool to check your eligibility.
Although some documented students qualify for "AB540" status, it is largely used as educational code for undocumented.
Unfortunately, not all educators are equally knowledgable about the rights and resources of undocumented students.
If you are talking to a college rep who doesn't know what you mean when you ask for information for AB540 students, ask to talk to someone who does!