If you no longer want to be part of a channel, you can easily exit it at any time. Leaving a channel will remove you from its member list, and you will no longer receive updates or notifications from it. However, you can rejoin a public channel later if needed. For private channels, you’ll need a new invite to join again.
Follow the steps below to exit a channel:
iOS
In the channel you want to exit, tap on the name of the channel to access the channel info.
Tap on
and select Leave channel.

You will be shown a prompt to confirm your decision. If you're sure you want to leave the channel, select Leave.

Thus, exiting a channel removes you from its member list, and you will no longer receive messages or notifications from it. If it's a public channel, you can rejoin anytime. However, if it's a private channel, you'll need a new invite to join again. If you left by mistake or change your mind, check with the channel admin for re-entry.