I suggest omitting the password during setup. Google is looking for the app password that it created, not the login password that you use for online access. After entering everything except password, press DONE and you should then see a Google prompt for the online password and, once accepted, will then prompt you to allow Thunderbird access. On clicking 'allow' Google will store a unique passcode for that PC.

tyvm i tried what u recommended but now get Warning Thunderbird detected a potential security threat and did not continue to live.thiunderbird.net if you visit the site attackers could steal info etc etc

THe live.thunderbird.net error happens when thunderbird attempts to show the welcome message. I don't know if that is an anti-virus issue or other interference. Are you running a VPN? Somewhere, there is something interrupting Thunderbird's startup.