I really want to go to a writing school but then i also really want to go to an art school cause i love art and it has always been my dream to be a artist and author so what am i supposed to do
Volunteer at a gallery and write for your local newspaper or blog. See how it feels and select the option that brings you the most joy.
Do both. Major in one minor in the other, or do o e take some time to save mo eh or whatever you need to do and then so the other! Education has no time limit!!
Ask yourself which one you want to get a formal training in. You can be an artist/author without going to school for it. Of course, going to school helps but there are other ways you can explore these interests by yourself. (Practice, workshops, webinars, etc.)