You do not log into Thunderbird. You log into your email account with your provider. Most providers have a way to reset a forgotten password on their email help page.

How do I get back into my thunderbird, it is asking for a password. the one I have is not opening the account. I simply want to open my Thunderbird account and need to reset the password.

There is no Thunderbird password. There are no Thunderbird accounts. Contact your email provider to reset your email password.