Using Trailhead and connecting to an account

I am going through Trailhead, largely the Salesforce Associate Trailmix. (I'm a PM working with SF SME's and so am not looking for in-depth knowledge.). I got to a module that wanted me to install apps and packages. It wanted me to Connect an Account and use Salesforce. I did not have a Salesforce account so I signed up for a 30-day trial.  

I got the email, verified the account, answered the questions. And when I go to connect to Salesforce it says (like it does anytime I do this with any software for the past 40 years) that it doesn't recognize me or my password. One minute after setting it.  

Do I need this 30-day trial? And why isn't it accepting my login credentials? I am using Edge and double-checked my credentials in the Password manager. They are spot on. But Salesforce refuses to acknowledge them. So, currently stuck in a doom loop.