SQL Server password

I hope you won't be able to get it as it would be a security issue!

I can still get into SQL Server Management Studio using Windows authentication.

You can try ShowPW.exe from http://www.scalabium.com
I suspect this is stored as an NT secret which you can get via SYSTEM account
https://www.experts-exchange.com/articles/30792/How-to-run-commands-using-SYSTEM-account.html

I provide this info assuming that you are authorized to use this system etc.

Unless you know some good hacker, you shouldn't be able to retrieve that password.
If you need to know the password to use it somewhere else, why don't you reset it? You just need to logon with another user that has administrator privileges to perform the password reset.

>>How can I get this password?

No you will not get the password directly. Some tool/technique may or may not help. But using that is not a very good idea.

Why you want to change it. ? Is there any requirement.

Agreed.

Reset the password is a better option.

#a42371033 works for a fact. See screenshot in #a42372260

Agree with Shaun's last comment.

Shaun's comment has the justification. His screenshot clearly shows the password.