To see the detail or even add a description to your folder, check out the steps:
Go to the location where your folder/file is stored.
Click on the “I” button on the top right side of the screen.
Click on the file that you what to see the details.
Get all the details about its storage, size, owner, last updates and the option of adding a description.
In case you wish to add any description, click on it and add it.