Realistically what colleges can I go to ?

I’m a senior with a 2.9 GPA and only took 1 AP class and it was only for one semester. I would have a better GPA, but I messed up in geometry where I received 2 D’s both semesters and in algebra 2 2nd semester I received a D also. I got a 19 on my ACT exam in which I did horrible on. I know I’m not going to go to a good university, but I sure would like to go to a decent one that would accept those grades somewhere in Washington or California.

I would suggest a community college to start where you can reset your grades and see how well you can do before applying to any universities.

I was thinking about doing that for two years then transferring to a university

A 2.9 is not stellar but far from community college. You’re a B/B- student, guessing A-/B+ but horrible at math.

What happened? Do you have dyscalculia? Did you not do your homework? Or did you spend less than 20mn a day on it? Did you get a tutor? Use Khan Academy videos? Ask your teacher for help? Do extra credit problem sets?

The first thing you need to do is improve that test score: commit to studying 1 hour a day on Grammar and Reading (borrow Melzer’s books from your library) as well as reading ACT for the bad test taker, plus one hour on Khan academy reviewing algebra and geometry. Register for the September test.
Are you registered for the August SAT? If not, it may be worth a try. Some people do better on the SAT, others in the ACT.

What state are your parents residents of?
What is their budget - have you run the NPC on T college nearest your home for instance?

What classes are you taking senior year?
See if you can retake those D’s through a class or online course because it’d increase your gpa. What math do you take senior year? You should try and take CP statistics.
Have you taken any honors class?
What are your areas of strength, academically?