Though you can only manage a settlement while in that settlement. Now you view statistics, manage settlers, tasks, and settings. Now you would go to a terminal and simply load your management holotape.This makes helping your people so much easier and fool-proof, instead of running around trying to track all twenty of your settlers to make sure they are working.
Settlement Management Software actually adds in a software for terminals that helps you control your settlement better! It adds control and significantly more than just barebones like food, water, defense, etc.