Cannot connect to gmail account

These are the two links Let less secure apps use your account - Google Account Help

Allow or disallow less secure apps to access accounts - G Suite Administrator Help

Click on cancel , close the background window of mail prefernces and quit the mail application , again open mail application and take the cursor on top menu bar > mail > add account > select google enter your web mail address > click on next and add password .

Then go to system preferences > internet accounts ( the box of mail will be checked its your choice to select rest of options contacts , calendars .....but you must check them also to utilise the features ) .

Try going to the Gmail website, access your account information, and look for a setting that allows connection to less secure apps. I don't know what the exact wording is.

Is your login password and keychain password are kept as different and your Apple ID is kept same as gmail ID , possibilities are your system keychain is corrupted , try to create a new user account How to test an issue in another user account on your Mac - Apple Support

And from the new user account configure mail account Set up Mail on your Mac with email accounts - Apple Support

Thank you for the links.

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