1-) Go to Google Search Console: https://search.google.com/search-console/welcome 

2-) Enter your website link under the URL prefix and click the Continue button.

3-) Select the option HTML Tag from Other verification methods. Copy the meta tag by clicking the Copy button.

4-) Go to your Site Manager. Then go to Configuration > Google Integrations > Google Search Console. Paste the meta tag you copied and save changes.

5-) After saving the changes on your site manager, return to the Google Search Console and click the Verify button and then click the Done button