Start with direction: two-way chat means a group, one-way publishing means a channel
A channel is a broadcast surface. Only admins post, subscribers read, and a bot there mostly publishes, edits or deletes on behalf of admins. A group is a conversation: members write, and a bot can receive messages, handle commands and reply to specific people. So ask one question first: does the bot need to process something users send? If yes, use a group or a private chat. If it only pushes announcements, prices or order status, a channel fits. Channel comments live in a linked discussion group, so a bot handling comments is working under group logic anyway.
Permissions: a bot must be an admin to post in a channel
To post in a channel, the bot has to be added as an administrator with the permission to post messages. Editing or deleting requires the matching rights, and each one should be ticked only if needed. In a group, a bot can receive commands and mentions as a regular member, but whether it sees all messages depends on privacy mode. Admin rights are needed only for moderation such as banning, muting, deleting or pinning. A workable rule: if it only publishes, give a channel bot posting rights; if it moderates, give a group bot a limited set of admin rights; never grant everything for convenience.
Privacy mode decides what a group bot can see
Bots start with privacy mode on, so in groups they generally receive only slash commands, replies to the bot and mentions. If the job requires reading every message, such as keyword monitoring or content review after join verification, privacy mode must be turned off in BotFather, or the bot must be a group admin. A common trap: changing privacy mode may not take effect for a bot already in the group, so remove and re-add it, then verify. During acceptance, send a plain non-command message in a test group and confirm the bot receives it, rather than trusting the setting.
Notifications: groups get noisy, channels push to subscribers
Notifications are where the two differ most. Channel posts push to all subscribers, who can mute the whole channel but not one type of message; admins can post silently to avoid a sound. In a group, each bot reply enters the chat stream, and in busy groups members often mute everything, burying important alerts. If a message must be seen, such as an order failure or a risk alert, push it to a private chat with the bot, or post only a summary in the group and keep details private. Putting critical alerts in a group is a frequent design mistake.
Typical scenarios and the usual choice
Announcements, prices and content distribution: a channel with a minimal-rights publishing bot. Support, order lookup and membership checks: private chat first, with the group as an entry point. Community management, join verification and spam control: a group, with explicit limits on kicking and deleting. Internal team alerts: a private group limited to team members, which controls visibility better than a public channel. Mixed needs are common, such as a channel plus a discussion group. In that case, state whether one bot or two is used and whether tokens and permissions are separate.
What to write into the requirements before ordering
Specify whether the bot runs in a group, channel or private chat; whether it must read all group messages and how privacy mode is set; which admin rights it needs, listed one by one; which channel carries critical alerts and whether silent sending is allowed; and who owns the group or channel and who can change bot permissions after handover. Acceptance should test permissions and notification behavior in a test group and test channel. Telegram features and limits change over time, so rely on the official Bot API documentation and real client behavior at the time.