There are many modules developed for PixelPost which can extend its functionality. You may find such modules in the PixelPost official website at:
Once you have chosen the module which you wish to install download its archive. Extract the archive which will contain a file having the name of the module. Upload that file in the “addons” folder of your PixelPost installation. You can upload the file using FTP or via cPanel > File Manager. Once you have uploaded the file go to your site’s admin area and activate the module via the “Addons” section.