That is called imposter syndrome and it is fairly common. You've already shown that you can do well with advanced subjects and college will be more focused on just chemistry. You'll take some gen ed stuff but honestly, no one really cares about your grades in those courses and you'll have such a large variety to pick from that you'll end up taking classes that you like and will find it very easy to get A's.
Now, this is coming from someone at a top tier Ivy doing their PhD in chemistry. It does not matter if you do your undergrad at Harvard or your local state university when it comes to getting into top graduate programs. What matters is your research experience and everything else that makes you unique. That said, go to the school where A. you will be happy and B. you will have the ability to do research at an undergrad level.
That means you're spending the next 3-5 years in a new place so you want to be excited to be there. If you enjoy where you live, you're going to be more inclined to get involved in things outside of school and those will help to shape you as a person. I'm not going to say that you're going to change a ton from this age to when you graduate but your ideas will mature a bit and you'll refine yourself some more and all of those experiences outside of school are going to influence that process. Go where you feel at home or to where you feel enchanted with the surroundings, it'll lead to a great time.
In regards to getting into grad school, which you very may well change your mind about in a couple of years... and it's completely okay if you do. (Plenty of people stick with a program because they want to finish what they start and they end up being miserable. It's not quitting if you change your mind, it's being able to adapt with new information at hand) But if you don't, you need to be doing research, the sooner the better. Make sure the chemistry faculty there is actively doing research and publishing papers in notable journals. You don't want to go to a place where tenure means they just teach and nothing more. That's great for them but terrible for you. Go to their research pages and look for recent publications. If none of them have anything within the last 5-10 years, I would be concerned. Next, find a couple people who's research sounds interesting at different schools and just shoot them a quick email saying that you're an incoming freshman and wanted to know if there are research opportunities for undergrads in their groups. (You may have to email the lab manager because sometimes the profs won't answer emails like this) If the answer is yes, I would put that on my list of schools to consider.
Research is everything in chemistry. Not prestige, not grades (to a point), and not big names. If you can crank out a paper or more as an undergrad, give some presentations, and win a couple awards if you're lucky, you're going to get into a great school. The difference between the people who are very successful and those who apply multiple times is simply research. Grad school is about lab work and if you haven't shown that you can work in a lab, no one is going to invest money / time into you because it's a massive risk.
The fact that you're thinking this far ahead as a high school student is impressive. The fact that you're thinking about carving your own path and doing something non-traditional is great! If your dad will support you, which will make your life so so much easier, and you can check all these things off, go to school wherever you want and enjoy the next few years. If he won't, stick with the schools he's listed as they are fantastic universities, go have fun in college, and keep it up.
Source: community college > state university > top 10 chemistry PhD program. Undergrad GPA 3.74, 4 papers published in ACS journals, 5 presentations, 6 awards, 1 scholarship, NSF GRFP recipient.
I was a pretty average applicant in terms of GPA and test scores but all the extras (research,presentations, publications...) completely opened doors for me and I essentially had my pick of programs at the end. Feel free to PM me if you have any questions.
Also, not putting stats to try and make myself look good, I think we all know that none of us care about randoms on the internet but I want to make the point that where you go and having a 4.0 are not the most important factor here. Research, research, research, and research are what get you far at this stage in the game.