What all can I do as a 9th grader to start planning and preparing for college? Is there anything I should know? Tips? From GPA’s to ACT or SAT to anything you wish you knew in your freshmen year? I’d really appreciate any feedback or advice that you guys have to offer! 
Don’t worry too much about the SAT or ACT yet- unless you find a subject you are really excelling in and want to take an SAT II (For example, biology or perhaps literature) I wouldn’t worry about standardized tests.
For freshman year, my main point of advice is keep it simple. I don’t mean don’t take honors/AP courses (of course you should be challenging yourself appropriately), but rather don’t worry too much yet about the college process. Enjoy 9th grade. Join lots of clubs and find a few that really speak to you. Maybe try out some community service. Play a sport. For freshmen year, what matters is that you get involved, and you keep your grades up.
Join activities because you like them, not just because they “look good for colleges”. You don’t have many opportunties where you have free music lessons, or an opportunity to get involved in drama, or ability to be on a team, etc etc. Take some initative and join things that expand your horizons but also that help the community.
Do well in classes, but don’t go crazy and drop band or something because it is unweighted in your GPA
Look at the book by Cal Newport, “How to be a High School Superstar”
Take a rigorous class schedule, do well, study for the PSAT when you’re a junior for potential National Merit.
Read a lot, get outside a lot, do things that truly interest you, not just things that “look good,” look at high school as something valuable in itself, not as a launching pad to college.
Yes to what everyone else said: freshman year is a critical year, but also one where it’s really important to not freak out or put too much pressure on yourself. Keep your nose to the grindstone, definitely, and do your best to acclimate to high school so you set yourself up for four years of success.
Join a bunch of clubs that you think you might enjoy, and use freshman year to see what sticks. It’s totally OK/normal for some clubs to fall away sophomore year as you stick with the ones you really enjoy/can make an impact in. I also recommend doing activities outside of school that you genuinely enjoy, whether that’s a sport, volunteering, something artistic (chorus, drama, etc.)–there are somethings you can’t do at school and it’s great to be well-rounded beyond your high school. And sometimes outside activities lead you down fun/unexpected paths.
Don’t think too much about standardized tests, generally, but do have an eye to sophomore year when you’ll need to start thinking about those (PSATs, studying for taking tests as a junior). If you think standardized tests may be a strong point for you, the suggestion of studying for the PSAT to gun for National Merit is an excellent one. But this path doesn’t suit every student.
And just enjoy the ride! Your main job freshman/sophomore year is to do well in your classes and slowly amp up your academic rigor (layering in more APs as you go), and engage in activities that you enjoy. Junior year is the time to really think about standardized tests, going for leadership and accomplishments in the activities you like the most, etc. Though if you see opportunities as a sophomore for leadership or honors, go for them.