How can i boost my chance of getting into UNC @Chapel Hill as a out-of-state student ?

Answered

A bit more background info about yourself might be helpful! You're obviously going to want to get the best grades possible while also challenging yourself academically. Remember that a "B" in an AP class isn't the end of the world and can look better on your application compared to an "A" in a typical class.

In addition to your grades you're also going to want to score well on the SAT or ACT. Of course the better you can score the more you increase your chances but I would try to definitely get in the 75th percentile or better. I know this all might sound like obvious information but your grades and test scores are some of the first things a college considers and if you don't meet there threshold your application won't get much attention, if any.

One of the biggest areas you can probably make an impact are your ECs. Think about what you enjoy to do both academically and outside of school and how you can incorporate those things into an EC. Generally speaking, most colleges will judge your ECs based on how much time was committed, how much initiative did you need to take to get/stay involved, what level are you involved at, and what leadership or responsibilities did you end up with. If you can think of a unique idea for an EC and can dedicate time and effort into it that might be enough to set you apart a bit depending on what else you have on your application. The EC doesn't have to be unique as long as you show that you're passionate about it. They all don't need to be related to your major either!

One final thing that could help. I know you said you're only a sophomore but you could start brainstorming ideas for your college essay. You need to write about something in such a way that the admissions officer can't get their essay out of their head. A strong college essay may not be the reason you get accepted to a school but a poor essay can most definitely be a reason why you don't get into a school. If the school is deciding between you and someone with almost identical academics, test scores, and ECs but you have a more memorable essay it could be enough to sway them into picking you.