Connecting external displays to 2021 MacBook Pro with M1 chip

Hi yes I did go through the articles I could find but the monitor (I used the apple monitor I have been using with my Late 2013 MacBook pro) using firewire to HDMI and it didn't recognize that monitor and then bought an LG with USBC connectors and used a USBC to USB C cable from my 2021 MacBook pro and again when I went to add monitor it didn't appear on the drop down. I had called apple tech support and the tech was really nice and helpful when trying to get the Apple monitor to work and he said its likely a monterey issue and to wait for the next update. But with a new LG monitor that has USB C and can connect directly to the new MacBook I figured this was easy. What I have done was plugged in the LG monitor when the MacBook was on, put it to sleep woke it up and nothing, then left it attached via usb c and restored the machine and again nothing, changed the usb c port on the MacBook as well as the external monitor and nothing. It appears the only way to add a monitor on monterey is to select the drop down there is no button that shows either monitor when plugged in. Sorry for the long response but it seems adding a monitor on this computer isn't as easy as it should be?

The latest cable I am is a thunderbolt 3 or 4 (not sure how to tell the difference). I didn't try closing the laptop and hitting any key as the display wasn't recognized when connected. This is very strange as apple products are usually plug and play. Also with the older MacBook and secondary apple monitor I tried using a thunderbolt 2-3 to HDMI cable to connect to the new 2021 mbp and nothing was sensed with that cable either. I would agree that it likely is me as that is typically the case but I am beating my head against the wall at this point to just get the monitor to be noticed. Thanks so much for your help I really appreciate it!

That may be the problem I bought the cable at best buy in the apple section to hopefully avoid getting the wrong one (appears that didn't quite work). Thank you for your help I am learning as I go! I appreciate your time!

Great questions the display is the 27 inch apple display and it has 3 usb A connectors, a thunderbolt (or thunderbolt 2) and a firewire 800 port. I tried using a USBA to HDMI cable to connect to the new laptop as it does have an HDMI port but the computer didn't sense the display. Thanks for your help!

and the monitor does have the main power cable and the thunderbolt and charge cable for the old laptop attached. I tried to pull the cable out as I seem to remember that I installed that, but couldn't pull it out. I used that so I didn't need to run the power to the outlet I am powering the old mbp using the power and thunderbolt pigtail. I had asked tech support if this could be causing the issue and he didn't think so as it was not connected. Do you think that could bypass the USB A to HDMI cable I am trying to use? I have a feeling that the Apple display may be too old to use with the new computer but i figured since it is apple also it should still work.

Thank you very much, I will try this when I get home.

I tried a USB A to HDMI cable and it didn't sense the display, that seems to be the most frustrating part all the cables I have used haven't allowed the mbp to see the display.

Perfect one more item crossed off the list thank you for your insight it is appreciated!

excellent thank you!

thanks for the insight!

thanks that may be just what I needed to get this going!

thank you for the insight!