Insert the Macro to one Page

In the page Edit mode in the Confluence, Click "+" button from the tool bar and select Other macros.

Find the macro by input "Easy Heading Free" and click the macro.

Then it will show the Macro browser window.

Click "Insert" button after you set the parameters for this macro.

The Macro item will appear on the page, you can remove it or edit it when you move mouse over it.

After Saving and Publishing the page, the Macro will work on this page.