The movie is where they are in an island and the leader wants the entire population to be super smart so they take a test if u fail I can’t remember but they either lock u up or kick u off and two close people get separated because one failed and the other passed
casspir Answered question Mar 6, 2020
Maybe this one?:
“The Thinning” (2016)
https://www.imdb.com/title/tt5254868/
They are not on an island, but the basic premise is similar to what you described.
casspir Answered question Mar 6, 2020