Getting to the right page to "Start a discussion"

Seeing some confusion about how to get to the right page for a Community where you can start a new discussion. e.g. Where / How to find "Ask a question" | Microsoft Community Hub Office outlook 365 .. where are emails saved? | Microsoft Community Hub I have to admit that it is not clear to me what the difference between these links is. Community Lounge | Microsoft Community Hub Tech Community Discussion | Microsoft Community Hub Why only one has "Start a discussion"? Why does a Web Search tend to land me on the one that doesn't have "Start a discussion"? Why the "Discussion Spaces" button on the one with no "Start a discussion" doesn't make "Start a discussion" appear or take me to the URL that does have  "Start a discussion"?