I am trying to implement Responsive UI Package for SharePoint on-premises (2013 and 2016) from this link
Now when I try to enable the feature using PS1 Script i get following error saying
The term 'Connect-SPOnline' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
PS1 Script to Enable responsive Package is