I'm currently a freshman is high school, and I haven't started doing any community service. I want to give back to my community but also incorporate my passions into it so that I enjoy participating in that. Specifically, something I've been doing for years is painting, and really enjoy it. Are there any ways I could incorporate that into community service?
Another item of importance for me is a way to give to cancer patients, as I have ties with that, but I don't know if I could find a way to include both.
I would meet with some of your towns representatives about a mural. Murals can help beautify your town. Plus it is something you like!
If you're close with some of your middle or elementary school teachers (specifically art teachers), then maybe you could talk to them about going in and helping them. You could also volunteer at a local hospital, and see if it's possible for you to work with cancer patients. Also, if you look up your city's name and "volunteer center", it's very likely that something will come up, and you can look on your city's website for volunteer opportunities.
Expanding on an idea given by @cheyennebare, you could ask to paint a mural at a hospital, counselors office, etc. While you do so, you could ask for donations to go towards cancer research, or something along those lines.
Volunteering as a graphic designer/ artist for grassroots organisation which works towards raising awareness might be a great way to start. Raising money through virtual fundraisers (drawing potraits for donars, a live painting session) may be another option to look into.
To keep this community safe and supportive:
You could organize an art drive/auction and give proceeds to your local cancer charity...