Your username for all things google (sheets, docs, drive, etc) is your email address and password.
Your work issued email address is first initial followed by last name, @northampton-k12.us, (Ex. gdoucette@northampton-k12.us) the default password for first login is 12345678
If you cannot login to gmail with the default username and password, please contact your administrative assistant or put in a ticket to IT here.