My best advice, given your young, is to explore other states besides CA. CA is expensive to live, rent, own, build, and the taxes are way up there and getting worse. I spent many years in CA when young due to work and then relocated cross country - on the corps dime (I was lucky to have that opportunity) and explored West, East, Mid-West, South West. After living all over the US, my wife and I have had no desire to go back to CA ever, despite it's beauty on the coast. The cost of living in every other place we have lived is far less, crime is less, quality of housing and education has been better, less traffic, pollution, have met wonderful, kind people (Inside - they could care less about what you wear, do for a living, or how much you weigh which is often front and center for lots of folks in Cali). I will say that we favor the ocean and lack of humidity in the West vs East and settled in the PNW. Though it is becoming very expensive...but we do love it.
Get out and explore the world - even if just in the US - before getting bogged down in debt so young. Lots of places and people to see and meet.
Have fun!