Add the link
In the event form, select Online next to Location.
Paste the meeting link, for example a Zoom, Microsoft Teams or Google Meet URL.
Leave Shorten URL on (the default) or switch it off.
Put a passcode or meeting ID, if you have one, in the description.
Save the event.
What Shorten URL does
With Shorten URL on, visitors see a CalendarLink short link such as https://calendarlink.com/link/LCxOn instead of the meeting URL. That short link always forwards to the meeting URL that is in the event at that moment.
This matters when the meeting link changes after people have added the event. Their calendar entry keeps the same short link, and it now forwards to the new meeting. With Shorten URL off, the calendar entry keeps the old link.
Change the meeting link
Open the event and select Edit.
Replace the URL under Online.
Save the event.
Other changes, such as a new time, do not reach calendars where the event was already added. See What happens when you change a shared event.
CalendarLink only shares the link. Waiting rooms, passcodes and who may join are set in your meeting tool.