Hi Julisa! I see a lot of great ideas posted here. I'll add that one of the best volunteer opportunities I had in high school was with the YMCA. I see there's a Y in Ventura https://www.ciymca.org/ventura.
I was part of a teen Leaders Club program. Many Y's have Leaders Club, but if they don't you might find opportunities helping with camp, swimming lessons, fundraising, dance, volleyball, etc.. We also helped with events like 5K runs and Healthy Kids Day. Eventually, I worked full time for the Y. After over 20 years, I'm doing freelance work in the community and am back to volunteering at the Y.
It looks like they have a 5K coming up in July with funds raised going toward their LiveStrong program that's for cancer survivors. https://www.ciymca.org/get-involved/volunteeropportunities/