Ok so I am a freshman at high school and I am wondering what are my chances of getting into duke or any UC colleges if I have 5 b’s total. I know that I am only a freshman but I am planning on graduating early at my high school and I am really worried about my stats so far. I have a 3.7 unweighted last semester and this semester I have a 3.5 unweighted because I took certain classes that were really hard, but however If I can get near perfect or perfect grades that next two years as well as doing good in other important college criteria like my test scores, extracurricular’s and college essay will I get accepted or at least wait listed on the “good side”. btw I only took 1 extracurricular this year but I am taking more next year, I took quiz bowl and my team went to nationals this April.
Well, the weighted/capped GPA that the UC’s use for admissions doesn’t include your freshman grades, only 10th and 11th grade. So you’re in luck on that front, if you do better from now on!
It’s really too early to say about super-elite private U’s. But there’s a whole world of wonderful colleges out there that ordinary mortals with B’s on their transcripts can get into. At this stage of the game it would be a better use of your energy to learn more about all the excellent schools outside of the the top 20. You can always raise your expectations later! In the meantime, get a good start on your UC GPA next year. 
Also try to find some extracurricular pursuits that are really meaningful to you, not just things you’re going to “take” for the sake of college admissions.
I’d recommend calculating your UC GPA (there are calculators online). UCs “round” your grades so an A- becomes an A and a B+ becomes a B, etc. This may or may not help your GPA. Since you are a freshman, just focus on taking challenging courses (but not too many) and having a high GPA. Luckily UCs don’t count freshman year. You can strive to get all A’s and A-'s because on the UC GPA that is a 4.0. Try and build your ECs now instead of waiting. My advice: create something. Find or create a leadership position. Do good in the world. Help others. Do something interesting.