You don’t need to do anything.
Now, all you have to do is wait for the Artistic Committee to meet in order to short-list the applications. The finalists will be announced on the date indicated on the homepage of the website, and in the rules.
2.7. The selection of finalists is announced no later than when the countdown displayed on the website of the Luxembourg Art Prize reaches zero. The announcement is made on the website, on social media and personally by email to the addresses submitted by the artist-finalists in their respective applications.