get error message when try to set up gmail

try this: Safari's Advanced tracking and Fingerprinting Protection. Turn off to enable adding the Google account. When done, turn it back on. See Can't connect Gmail to Macmail (Sonoma 14… - Apple Community for the posted solution in Apple Community.

This support thread should help.

https://discussions.apple.com/thread/254659965?sortBy=best

That does not change the meaning of the error message. If the steps provided do not work for your situation, then it is something Apple themselves would need to fix, and no one here can change that.