The part library manager gives you options to edit your list of part libraries:

With some options to copy/delete/add new parts you can manage your libraries here and manage the available libraries in the settings dialog:

The library types containing data from the open Job/Design, local types like xml or lite DB and online types like API Part Libraries, REST Libraries and out 365 Libraries:

With the context menu you have options to copy or edit the part, you can export the library list and search for specific information:

Here is an short video how to bring parts in your library:

use the pencil button to edit part properties in an seperate dialog:

Depending on the library type there are different properties available, with 365 libraries you can manage your properties in admin area or in xml library you can directly change the available properties.

The Part Library Outline Editor is similar to the Package Editor, you have also all edit options from there:

For more information check this page here