I’m not sure if I need to do more research

but I have a Python program that steps through the 85,000 messages in a group and when it finds media from a single hard coded username it forwards the media to a separate group for archiving. I could save a lot of time if I could search for the user manually and get the message_id of the first photo or video in the list and start my program there. I tried forwarding the message and capturing the message_id in the target group but it gave me the id in the target and not in the source.

Is there a way to pick a message in a large group and get the message_id of that message?

It takes a day to step through the 85,000 messages and sometimes the user’s first posting has a message_id above 60,000 so I am looking at a lot of useless messages before I reach the first good one.

not with bot api. you could try workaround using an mtproto library like Pyrogram.

I’ve used Pyrogram before. Can you give a little more of a hint? Could I capture the message_id at the source when I forward it if I can get permission to install a bot on the source?