I am unable to update my Adobe Flash player. I set up an account, I know my ID and password (I just set it), but I can't sign in to complete the download. HELP!
You don't sign in to download. I expect it needs your computer's password, the one you chose when you first switched it on. Be sure you recognise the various password prompts so you aren't in danger of being scammed by bad people stealing passwords and personal details or worse.
Below link might be helpful:
This is the OS, not Flash Player prompting for the password, as such, it's whatever you use (with admin permissions) to log into your system. see What userid & password do I need to install Flash Player? for more information