If you wish to start a video meeting, you don't need to specifically create a calendar appointment and invite the other guests to the event. Instead, you can start a meeting in your browser, then invite other people by sending them a link to the meeting.
To start a meeting via the Google Meet app in Google Workspace:
Click on the App Launcher near the top-right corner of the screen
Click on Meet
Click on the New meeting button
Choose Start an instant meeting
Click on Continue
A new meeting will open - click on the Join now button:
Once in the meeting, click on Copy Joining Info to copy the meeting link, which you can then email to the colleagues you wish to join the meeting.