A hosting package is simply a set of functions, limitations and resources each cPanel account may have within a Reseller Hosting Account.
Basically, having different packages with a different set of functions and limitations allows to provide a range of hosting accounts based on particular features.
NOTE: It is recommended to configure a hosting package prior to creating a new cPanel account in WHM to simplify further cPanel accounts management process.
To create a new package in WHM, you will need to do the following:
1. Log into WHM using http://domain.com/whm or https://hostname_server/whm
2. Navigate to the Add a Package menu in the section Packages
3. Set appropriate quotas in the Resources section
4. Choose required settings for the package in Settings, including Feature List
5. Click on the Add button: