First, you need to identify your site URL which is indexed in search results. The command to check all your indexed URL's is site:www.example.com.
All the results are shown for your site.
In order, to remove the URL's which are of no use or which contains old content first thing you need to delete the page & redirect that particular URL to the contact us page.
After few days when the site has again crawled again check whether the deleted page appears on the search results or not.
If it again appears you need to remove that page from GSC.
Steps to follow:
- Login to your webmaster accounts.
- Select Google Index.
- You will get a drop-down menu with 3 options i.e
A. Index Stats
B. Blocked resources
C. Remove URL's
- Select Remove URL's
- You'll get a new window that is with a button named as "temporarily hide".
- Click on the button and paste the URL and click continue.
- A new window will be triggered with a drop-down menu of 3 options.
- Based on your requirement select one option and continue.
- After a few days, you need to check the status in webmaster tools whether the page is deleted or not.
Is there a reason you're not adding 'noindex'
-noindex
can be VERY slow. Beside of this, Google revisits noindexed urls to get into knowledge, whether they are indexed again. 410 works once and forever.