Head to the Settings tab of your forked repository and click on the Security > Secrets and variables > Actions

Add the following variables by clicking on the New repository variable button in the Variables tab.

• SITE_URL: The URL of your site. (if you have a custom domain, you can use it, otherwise you can use the one that Cloudflare provides you.)
• SITE_TITLE: The title of your site.
• SITE_DESCRIPTION: The description of your site.
• SITE_LANG: The language of your site. (e.g. en, zh-TW)

Note: If you want to use the url that GitHub provides you, it should be like this: https://<username>.github.io/<repository-name>/. Don’t forget to set the SITE_URL variable to the whole URL including /<repository-name>/, or the page deployed will not work properly.