Will studying abroad for a semester in high school help my chances of getting into college?
It will not get you into any place that you are not otherwise qualified for.
This only case in which this might help is if you’re looking to study in that country as a college student for the whole program.
Just from reading your app it will be impossible for your university to judge the quality of your program abroad. It’s also worth waiting until college to go abroad. As an adult you just have a lot more control over your experiences in general, but there will be more interesting programs specific to your field of study as well as scholarships to help finance your trip.
It can help if it advances your foreign language proficiency and if the experience is portrayed well in your college applications (eg, such as fostering a desire to study International Business or International Relations).