Why doesn't it work when adding a bot to a channel (Telegram)?

Question

Bots

When adding any bot to a channel (regardless of whether it is public or private), it does not react in any way.
It was necessary to find out the chat_id of the channel, for this I added a couple of bots - none of them reacted
. At the same time, adding them to groups - they work there.
Someone tell me what could be the snag and where to look to solve the problem?
P.S. bots are added as administrators with full rights

Answer 1

If the bot has the Group Privacy option enabled, then it does not see messages in it. It must be turned off.
BotFather - Bot Settings - Group Privacy.
upd: Although, of course, the matter is different, we are talking about channels, channels are not groups, there is a different method for processing messages.

Answer 2

I partially solved the problem of the need to get the chat_id by looking at the web version of the telegram
on the old version, the link https://web.telegram.org/?legacy=1#/im?p=c16818548...
from p=c and before _ we get 1681854893, add the prefix "-100" and get our chat_id
-1001681854893
if anyone needs it