How to add a bot to a Telegram Group?

You have to use @BotFather, send it command: /setjoingroups There will be dialog like this:

YOU: /setjoingroups

BotFather: Choose a bot to change group membership settings.

YOU: @YourBot

BotFather: 'Enable' - bot can be added to groups. 'Disable' - block group invitations, the bot can't be added to groups. Current status is: DISABLED

YOU: Enable

BotFather: Success! The new status is: ENABLED.

After this you will see button "Add to Group" in your bot's profile.

Edit: now there is yet an easier way to do this - when creating your group, just mention the full bot name (eg. @UniversalAgent1Bot) and it will list it as you type. Then you can just tap on it to add it.

Old answer:

1. Create a new group from the menu. Don't add any bots yet
2. Find the bot (for instance you can go to Contacts and search for it)
3. Tap to open
4. Tap the bot name on the top bar. Your page becomes like this:
5. Now, tap the triple ... and you will get the Add to Group button:
6. Now select your group and add the bot - and confirm the addition