Is “cbsearch.site” a web robot, and if yes, how do I block it?

I saw invalid traffic in my Google AdSense account. I read some articles from the web, which all made it clear that invalid traffic could be caused by web "robots". So I tried to read on how to block these robots from my website. Some pointed out to look through "access logs" (which is very very long and frustrating), or use Google Analytics (Acquisition > All Traffic > Source/Medium) to identify unusual traffic.

In doing so, I found out that cbsearch.site is/was a referral to the site in the Google Analytics.

According to this article:

cbsearch.site – deceptive search site that infiltrates PC without user consent and affects Google Chrome, Safari, Mozilla Firefox or Internet Explorer.

My questions are:

  1. Is cbsearch a robot?
  2. If yes, will it be advisable to block and how do I block it in .htaccess or robots.txt?
  3. If no, are there other ways to identify what is causing the invalid traffic or are there any common activities that do that?