Sophomore
Wants to study chemistry at an Ivy League School
Just because you want to study chemistry in a university doesn't mean that you can't pursue other interests. You should participate in language Olympiads if it's your passion. However, if it's just a suggestion from someone for building a resume and you don't like it, you'd rather opt out.
In the US system you typically apply for a university, and not a major. As a general rule, you cannot really "choose" to study chemistry in your application; you can only indicate your interest to pursue chemistry as a major later on. Seeing as this is the case, if you genuinely enjoy linguistics, I say go for it. You can choose to not include the linguistics olympiads later on in your application if you think that they don't add anything to your portfolio, but I think they'll make you a more interesting applicant.
To keep this community safe and supportive:
The fact that you wish to major in chemistry at university does not preclude you from pursuing other interests in addition to chemistry. If competing in language competitions is something you enjoy doing, you should look into joining one. On the other hand, if it's merely a piece of advice from someone else https://slope-game.io/ about how to construct a resume and you don't like it, you might want to pass on it.