im trying to play multiplayer on quake ii remastered but cant find the login to bethesda button anywhere like in quake i remastered. Please help me find out how

Suggestion A: Forget the crappy ports and throw yourself at the mercy of a source port instead.
Suggestion B: Do what we all did in the old days, and forgo accounts. If you can't just jump into multiplayer with a username and a prayer, then it's a bad port.
Suggestion C: Check the Quake series subforum. Chances are, the solution might be there.

Helpful as ever...not.

Bethesda ditched its launcher a while ago and there was a process to convert games to a Steam account.

That automated process was time-limited though AFAIK and is probably shut down now so you might have to contact Bethesda support with your account details and have it switched over manually.

https://arstechnica.com/gaming/2022/04/so-long-bethesda-launcher-heres-how-to-move-its-games-to-a-steam-account/

no i bought quake ii on gog for the first time, i dont know how to log in too bethesda

You need to launch Quake II with Galaxy to be able to play Online multiplayer, no need to login with a Bethesda account. Also be sure to enable crossplay in Options if you want to play with console or Steam users.

For Local or LAN multiplayer, you don't need Galaxy nor a Bethesda account.

Yea but thats the problem, there is no way to get GOG Galaxy on linux and thats what i use. Is there anyway to spoof the servers to think i have gog galaxy?

I think there are third party apps for Linux that can be used as Galaxy replacement, but never used them so I don't know if they are multiplayer compatible.

Launch Quake II: Start the Quake II game on your device.

Access the Menu: Once the game is running, navigate to the main menu or settings menu within Quake II. This is usually accessible by pressing the Esc key or selecting a menu option from the game interface.

Find the Bethesda Account Option: Look for an option labeled "Bethesda Account" or "Login" in the game menu. This is where you'll enter your Bethesda account credentials.

Enter Your Credentials: Select the "Bethesda Account" option and enter your Bethesda account username (or email address) and password when prompted. If you don't have a Bethesda account yet, you may need to create one first.

Login: After entering your credentials, select the login or submit button to log in to your Bethesda account within Quake II.

Access Online Features: Once logged in, you may gain access to online features, multiplayer modes, or additional content associated with your Bethesda account.

If you encounter any issues while trying to log in to your Bethesda account in Quake II, double-check that you're entering the correct username and password. You may also want to ensure that your device is connected to the internet and that Quake II's servers are operational. If problems persist, you can reach out to Bethesda support for assistance.
https://webcammictest