General getting started

[James Good]

This not at all clear,, are you trying to boot emmc or SD, do you have some boot at all?
Some generalities
1) check that what you are  typing is what you are getting, type password in 1st field
Don't hit enter, backspace it away, also check root password
2) if you remember root password, that is the easiest. root can change any password,,
passwd $USER  and follow prompts
3) the nuclear option, blank password by editing etc/shadow (on right device)
field separators are ":" (colon),, make 2nd field blank (ordinarily 40-60 chars, hashed password)
as so,,,,,root::more fields OR $USER::more fields

Actually, there are at least two problems I am having with the laptop that you have mentioned: eMMC and the passwords (both root and user).  When I ordered the PBP, it came standard with 64GB of eMMC installed but with a 128 eMMC module available as an option.  I ordered that option, but have not yet installed that module.  The passwords are a more pressing issue for me.  Simply because I am not able to get to a terminal screen on the laptop to make the changes you suggest.  At one time in the past, I thought there had been a key or key combination that could be pressed at power on that would bypass the login screen and restart the initial 'first boot' sequence where you (the user) would set the time zone information, the keyboard layout, the desired language, then the username and the user password.  The original password, if memory is correct, was 'root' but even that does not help getting into the laptop.  Thank you for the suggestions here.  I will print them for future help if needed again.
James Good