The Microsoft 365 Admin Center is the front door: users, licences, groups, domains, service health, and billing. Everything deeper hands off to a specialised portal — Exchange admin for mail flow, SharePoint admin for sites and sharing, Teams admin for policies and meetings, Intune (Microsoft Endpoint Manager) for devices, Defender for threat protection, Entra admin for identity, and Purview for compliance and retention.
When a ticket arrives, name the owning console before you start clicking. 'Email from a supplier is going to junk' is Exchange and Defender. 'A user can see a folder they should not' is SharePoint. 'A user cannot sign in' is Entra. Guessing across consoles is where an hour disappears.
Licensing is the quiet trap. Business Basic has no desktop apps; Business Standard adds them; Business Premium adds Intune, Entra ID Plan 1 and Defender for Business. Frontline licences suit field or shift staff who mostly use a phone. Assign licences by group where possible so onboarding is one group membership instead of six checkboxes.
Check Service Health before you troubleshoot anything that broke for everyone at once. A five-second look at the health dashboard has saved thousands of wasted technician hours.