You can add a calendar to a channel that can be used to schedule events for everyone in that channel to see. Open the channel and click the + icon to the right of the tabs at the top of the channel, which opens the “Add a tab” panel. Click the Channel calendar icon. (If you don’t see the icon right away, start typing channel calendar in the search box.) Then type in a name for this new calendar and click Add.
When an event is added to the channel calendar, a summary post is created in the channel.
To add an event on a channel calendar to your own personal calendar, open the event on the channel calendar and click Add to calendar.