This is the 4742nd most frequent Russian word.
закладки
Bookmarks.
In this sentence, 'закладки' refers to bookmarks in a web browser or physical markers used to keep a place in a book or document.
Я добавил эту страницу в закладки.
I added this page to bookmarks.
Here, 'закладки' specifically means physical bookmarks utilized to mark pages in a book.
Я нашел старые закладки в своей книге, которые использовал в школе.
I found old bookmarks in my book that I used in school.
In this context, 'закладки' refers to bookmarks as physical or digital items for marking reading positions.