...
On your Google Calendar, click the Create button at the top of the screen.
Enter the appointment/event name and purpose and choose whether you want it to be an event, an appointment, etc.
Name your event.
Choose the time range you’d like to schedule.
Choose whether to invite guests, reserve a room, add video conferencing with Google Meet, etc.
Save your appointment and Google will add it to your calendar and the calendars of any guests.
...
How Saving Works in Google Drive
There are a few options for saving docs and files in Google.
While you are online and working on a file, Google will automatically save any changes and updates.
However, Google also saves versions whenever significant changes are made.
You can make copies of any version of a file you want to keep for further reference from the version history tab.
...