The user experience in Confluence is slightly different than in Reports or in Jira Dashboards and depends on the platform you use - Cloud or Serve/DC.

Cloud

How to add

Step 1. Create a page and click on “+” to add an element to the page. In the opened dialog, you can start typing the name of the gadget to find it. To add a gadget, click on it.

...

Expand
title You may meet with the authorization dialog. Expand for more details.
It could look like this because your Jira instance doesn’t have automatic authorization enabled: Image Added After you click the Next button, you need to select your Jira instance name from the menu and click “Accept". Image Added At the end of this process, you have to reload the Confluence page and start adding the gadget from the beginning.

Step 2. Select the target chart and click on “Create chart.” FYI: You can scroll the dialog.

...

How to edit

Server/DC

How to add

...

How to edit

...