I’ve been trying to solve this for three days and none pf the solutions I’ve found online seem to work, so I am going to have to ask for help.

I want to create a Telegram "Group Chat" to be used by members of a club I’m in. I created the chat named with the initials of the club, like: "ABCD" and added some members. Now I want to automate the sending of occasional messages to the group for all members to see. Weather forecast, random photograph from our gallery, etc.

Using @BotFather I created a bot called "ABCDbot" and noted the token for that bot. Now I have two "ABCD"s on my browser left side-panel. Selecting one gives me "ABCD bot" and selecting the other gives me "ABCD 123 members".

Using a perl script and LWP I can send a photo using

#!/usr/bin/perl -w

use feature 'say';
use LWP;
my $api = LWP::UserAgent->new ();

my $chat_id = '1234567890';
my $photo = '/home/user/gallery/photo999.jpg';

my $response = $api->post(
  "https://api.telegram.org/bot<ABCDbot's token>/sendPhoto",
  [ 'chat_id' => $chat_id,
    'caption' => 'Photo Randomly Selected by the gallery',
    'photo' => $photo,
  ],
  'Content_Type' => 'form-data',
);
if ($response->is_success) {
  say "Response..... Success!";
} else {
  say "Response..... Failure!";
}

This works, providing I give it a legitimate chat_id and a legitimate file to send.
But the trouble is: I can’t find the chat_id for the group chat with 123 members! Every method I’ve tried now proves to be obsolete or simply doesn’t return the desired chat_id for the ABCD group chat. I can get my own chat ID or that of individual members of the group, or of the bot itself, and can successfully send photos, messages, etc to those destinations, but I just can’t send anything to the group.

Can anybody walk me through the process of getting the chat_id for my group chat? Or direct me to a document describing an up-to-date, working method for obtaining same?

Assistance much appreciated.