The nofollow tag is a tag that tells search engine crawlers that "this link should not be crawled."
In other words, if you add the nofollow tag to a link that is subject to purchasing directors mailing lead a penalty, the crawler will not crawl it, so the quality of the linked website will not affect the SEO evaluation of your website.
Reference: Search Console Help: "Using rel="nofollow" for specific links"
3.
In fact, there are two types of penalties : automatic penalties and manual penalties , and the subsequent steps vary depending on the type.
First, let’s check which penalty you received. Log in to
Google Search Console and open the manual actions for search traffic .
Google Search Console Images