If you want to update or replace any missing links in your InDesign file, you'll need to open the Links panel. You can open it from the Window menu, or you can use the keyboard shortcut (Ctrl/Cmd+Shift+D).
In the Links panel, any links that are missing will be flagged with a question mark icon, and you'll also see a small arrow icon that tells you the original source location of that link.
If you want to relink the missing file, all you need to choose is the File > Relink command, or select the link and choose Relink from the Links panel menu. From there, you'll be able to find the file you need, and relink it to the document.
InDesign will automatically update your document with the new resource and it should look just like it did before. Remember to always keep your original files in a safe place, in case you ever need to update the links.