How to even physically make an account to log in and begin? I feel like I'm going crazy

Sorry if this is an easy question, but I’m literally tearing my hair out after 3+ hours of trying. I attached a picture of the furthest I was able to make it. I never made an account, and have never seen an option to make an account. Where am I going wrong?

It’s the one you set during installation. The default username is admin.

Thank you for the fast reply! I think I might have accidentally changed my user and password with the command prompt when I was trying last night, but now I don’t know how to reset it. I just get an error message.