Apple Mail, Gmail and OS 10.13.2

Upon installation of High Sierra on MBP my one Gmail account in Apple Mail went off line and began asking for a password. I tried the existing password, then set a new password via the gmail server and added the new password to the gmail account all to no avail. I have jiggered so many settings now that the action that makes the most sense is to delete and then reestablish the account. However, the settings in 10.13.2 Mail (v11.2) don't exactly match the tutorial on the Gmail web site. Any thoughts?