Nanoflow Commons were introduced later then Mx version 7.23.2:
You will not be able to import it into any version previous of Mx 8.0.0. If you try to import it into any previous version, you will see this:
What you can do is download nanoflow commons from the appstore: https://marketplace.mendix.com/link/component/109515. This will get you nanoflowCommons.mpk in your download folder. Unzip that file and you will get:
Tims answer is technically correct.
But as you are taking a learning path of Mendix you should not use 7.2 but 9.x
Are you following the learning path via https://academy.mendix.com/link/path/31/Become-a-Rapid-Developer or with other resources?