Don't yet see 'Network Setup has been added underneath your Tools menu item'

Hi - am following the steps in the beginner's manual and have edited the wp-config.php to
define(‘WP_ALLOW_MULTISITE’, true);

however, I don't see the Network Setup link under the Tools (even under Network Admin)
and hence the options to choose either sub-domains / sub-directory is not available / visible.

makes me wonder...
- is it because I've setup the wordpress using Softaculous?
- is there something that I still need to do via the CPanel?
- am I missing something?

BTW - I'm a total novice, so...