Yes, Calendar has event notifications and personal reminders. You can set up an email notification for an event or create a reminder to send you a notification. To add event notifications and personal reminders, see Get started with Calendar.
Yes, you can send meeting invitations to any email address.
If your event has a large guest list, you can invite the attendees through Google Groups. Groups lets you invite up to 100,000 people for an event. If you invite a group to an event, new group members will be automatically invited when they join, and members who leave the group will be removed. You can see individual responses for large guests lists by exporting the guest list to Google Sheets on the web.
Visit the G Suite Help Center for more information about guest limits for invitations.
Note: If you change the color of an event, the original color is represented as a vertical line on the left side of the event.
Note: Deleted events remain in a calendar's trash for approximately 30 days.
If the event organizer hasn’t given you permission to modify an event, you can't make changes to the event time or its duration.
Yes, if you install a particular third-party conferencing add-on, you can add a third-party conference to a Calendar event. To learn more about third party conference add-ons, see Get extra Calendar tools.