How can I know how many people accessed a folder or file on Google Drive or Google Photos that I shared with a link?
Share the folder or link through Google URL shortener (goo.gl). If you login to create short URLs, it always show all short URLs created through your email. You can check the detail of clicks from the given list of short URLs.
Even if enter
.info at end of the short URL, it shows all details about link. Meaning, if the short URL is
goo.gl/QZ3qT7 then enter
goo.gl/QZ3qT7.info in the URL bar and you will see number of clicks on link and other details as in screen shorts.