Caldav is a protocol that allows different clients/servers to access scheduling information on remote servers as well as schedule meetings with other users on the same server or other servers. It extends WebDAV specification and uses iCalendar format for the data.

Fetch Microsoft Exchange calendars and availabilities using Exchange Web Services (EWS).

Import events from an ICS Feed into Cal.com.

Microsoft Office 365 is a suite of apps that helps you stay connected with others and get things done. It includes but is not limited to Microsoft Word, PowerPoint, Excel, Teams, OneNote and OneDrive. Office 365 allows you to work remotely with others on a team and collaborate in an online environment. Both web versions and desktop/mobile applications are available.

Zoho Calendar is an online business calendar that makes scheduling easy for you. You can use it to stay on top of your schedule and also share calendars with your team to keep everyone on the same page.