You want to find your friends on MS Learn and follow them but using search you can’t find your friends!
Navigate to your profile on MS Learn. Click the Q&A link at the top of the page.
Click the search button (you don’t have to enter anything)
Now on the right-hand side you will see “Refine Your Search” about the middle of the page.
Check Users and uncheck everything else and click Refine Search.
Now back on the search page you can enter a username and the user will be returned. To follow them hover over their username and click the button in the tooltip.