Reviews are how new readers find a book, and readers who enjoyed one are most willing to write a line or two just as they finish it. On an edition's Back matter tab, turn on the review request: the studio adds a page right after the story, in the edition's language, with a heading, a sentence or two (yours, or the studio's) and where to leave the review.
Where it sends readers: one ebook goes to every store, and a link to one store could keep it out of others: Apple Books doesn't take books that promote another store, and Kobo turns away ones that link to businesses. So the page doesn't link to any one store. It links to the book's review page, a part of its book page: the stores the edition is live in (as its Uploads tab says), each at the reader's own country's storefront, opening the book where its review form is. Readers choose the store they bought it from. In print, the page shows the review page's address.
Turn on the book page first. Without it, or for an edition you leave off it, the page asks for a review in words alone. The page is written into every build, so turning the book page on outdates the builds made before.
What you need: the Author plan, or a Book Pass for the book.