Google uses clicks and click duration to measure search quality, which affects how documents are scored, and in turn may affect how they rank. User interaction data has played a significant role in how Google rates the quality of its results.
A former Google employee admitted this and more about the extent that Google uses user data in a testimony given in September (Google v USA).
Here's the full court transcript
I covered this last month (not self promo, can't find another source):
Witness Testimony Highlights the Significance of User Data in Google’s Search Algorithm
Here are some slides from Google is Magical, an internal slide deck from 2017.
Here are two articles by Bill Slawski that detail some relevant patents:
User Click Through Rates and Search Result Rankings at Google
The Long Click and the Quality of Search Success