The Instructor was trying to set a page they created as the home page for their ELMS-Canvas course. This option was "greyed" out.
The page was not published; the option was not available.
To set a page as the home page for your ELMS-Canvas course, you will need to go to the "Pages" section of the course, select the three dots to the far-right of the page, and select "Make Front Page" from the drop-down menu. If the page is not published, it show a circle with a line through it and the page will not be able to become the front page. To publish the page, you click on that circle with the line through it and it'll turn green.