Microsoft 365
Exchange admin center URL
https://outlook.office365.com/ecp/ (old)
https://admin.exchange.microsoft.com/#/homepage (new)
Login to webmail
https://outlook.office365.com/
Admin Area
https://admin.microsoft.com/
Domain DNS settings (MX/SPF)
https://admin.microsoft.com/Adminportal/Home#/Domains
Host DNS with Microsoft
https://portal.office.com/Adminportal/Home/#/Domains/Details/YOURDOMAIN.TLD
Setup DKIM
https://security.microsoft.com/dkimv2