How can I create channel or group in Telegram
Reference :
Creating Group
Open the Telegram app or go to Telegram Web.
Click Edit Menu icon.
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From the menu, select New Group.
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Choose the contacts you want to add to the group.
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Tap Next
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Set up the group details, such as the name and group photo.
Tap Create/next to finalize.
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Steps to add bot to group and retrieve group IDs
Creating Channel
Open the Telegram app or go to Telegram Web.
Click Edit Menu icon.
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From the menu, select New Channel.
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Add members.
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Set up the channel details, such as the name, description, and channel photo.
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Your channel is now ready to post content.
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Steps to add bot to channel and retrieve Channel IDs