A simplified steps on how to remove a website/property/URL from Google Search Console or webmaster tools. A few reasons could be you don’t own the site or domain anymore that can through selling or expired.
1 (one) Google Search Console account which you created using your Gmail account can have around 1000 (one thousand) websites give or take.
In a tweet by Google employee Gary “鯨理／경리” Illyes on October 28, 2015
FIRST, Login or go to your Google Search Console dashboard.
If you have multiple sites click on the triangle next to your domain to expand with option and choose your preferred website you want to remove or delete
SECOND, Scroll down the options section which is on the left side of the interface, choose settings and click on the remove property button under property settings
LASTLY, A popup page which says remove property will be shown and click on the remove property text option