Here is how to recover your lost bookmarks (Windows):
Copy C:\Users\%username%\AppData\Local\Google\Chrome\User Data into File Explorer.
In search bar, type Bookmarks, you will see a list of files named Bookmarks and/or Bookmarks.bak. (Note: If there is more than one user using the same Chrome, bookmarks from other users will be listed too)
Select all the files with mouse and drag them to the upload block from the link here https://rongjiecomputer.github.io/chrome/bookmark-recovery/#windows.
Download all the HTML files.
Open each HTML file with Chrome and determine the HTML file that contains your bookmarks. (Note: The largest file is most likely the correct one)
In your Chrome browser, click the Chrome menu icon and go to Bookmarks > Bookmark Manager.
Click the menu icon beside search bar and click "Import Bookmarks".
Select the HTML file that contains your bookmarks.
Your bookmarks should now be imported back to Chrome.