Manager is missing from Extentions

[canabanana]

I'm brand new to Joomla. I came across JSN PageBuilder and tried to install it using linux mint but without success. My first issue is that "Manager" is not installed under "Extensions" and I can't find support for that anywhere. Your help in fixing this would be most appreciated.

Thank you

[toivo]

How did you install your site? If you downloaded the latest version of Joomla from https://downloads.joomla.org and installed it, you would have had to enter a username, which automatically gets full access as Super User. Full access includes the install option for extensions, Manage - Install.

Are you logged in as Super User?

Is the site hosted on localhost or a remote server? Are you perhaps using a demo site with restricted features?

[AMurray]

As with @toivo's comment, Super User is the only one with ability to install extensions unless you change them, from the default settings.