@coolguy40 , I agree with most of that, except it isn’t a lottery.
OP, I encourage you to think about what’s going to make you happy in the long run, rather than fretting about what is a slim possibility. If your parents are supportive and you can make it work with your schedule, by all means, go to the foreign country where you don’t speak the language. I’m remembering yet another student I know. She lives in Australia (now a junior at university) and as a second-year high school student, did a semester in China. She loved it too, as most students seem to.
It is not too soon to start planning study abroad as a high schooler, if you are up for the challenge.
Summer experiences can be fantastic, but they are not a substitute for the student who wants a more immersive experience. So ask yourself what you want out of study abroad. Six or eight weeks is not like a span of several months. I do agree that if it’s simply a case of thinking it would be cool, without having a deeper understanding of potential issues that might arise and solid reasons for wanting to do it, you need to think it through with the help of your parents.
Returning to the question of “will doing this enhance or weaken your app to tippy tops,” there’s no definitive answer. A student with top grades, scores, essays and ECs isn’t going to be dismissed out of hand for studying abroad. You will probably want to engage in some ECs while you study abroad, because simply being a tourist for a year of high school won’t impress top colleges. Build a couple of of solid relationships with teachers not junior year so you can get good recs for college.
In short, I absolutely think you should not pass up the opportunity, if it is going to work for you. Honestly, by the time you are a junior, you need some good match and safety schools anyway, so don’t get hung up on tippy tops.