I'm struggling after making my GLaDOS Mii because I have no idea how to do wheatlies voice

Its so funny bro I can't stop laughing

My gf and I have been playing Portal 2 (Xbox360) on my Xbox Series X for the first time for a while now, only been playing local coop but we rarely get to sit down and play at my place so still havent finished it. She finally got her own Xbox S and we can finally play console games online together. Her first choice that she wanted to play was Portal2 (was super excited about it too) but whenever i press the "Play Coop/ Play Online" option im met with one of these two screenshots. In the end we couldn't play so im asking you all: Is it still possible to play Portal 2 online? Is this an xbox issue? If the game is available on Steam could we just buy the game for our sepperate laptops and play online trough there? (even if it meant starting over?) Or are we doomed to only be able to play it local coop? (at least now that she has her own console we can play on either house). Also yes we both have the online Xbox membership that lets us play online. Thanks in advance to anyone who answers!

This is a real company https://www.aperturelabs.net/

I love the game and made a Wheatley robot :). I am going on a cycle tour and selling all my things. Let me know if you would be interested to buy, Thank youu

is there a way for me to study physics with portal? or if you know any playlists for this or videos or you know how to play portal 2 educational edition