As an administrator, you can make some additional blocks available so that users can add them to their personal dashboard (see Customizing the dashboard).
You first have to create some blocks (in the standard Drupal way, at /admin/structure/block).
Then in the Administration menu click on "Dashboard management":
The interface is the one below:
All the available blocks on your Opigno instance will be listed. You can select the ones you want to make available for the Opigno dashboard by checking the option in "Available" column.
In case you want to prevent users from removing one block from their dashboard, you can check the option in "Mandatory" column.
By clicking on "Default configuration settings" tab, you have the possibility to manage the default display of dashboard.
To do that, click on the button "Set dashboard blocks", then arrange the blocks like you want them to appear by default for new users.
Alternatively, you can click on the button "Restore all users dashboard to default configuration" if you want to alter the dashboard of all users to match the default dashboard that you defined.