I’m confused about what log in information is requested to fill out the initial add-in urls. Do I have to use my Bitwarden login first, then add the site I want saved?
@CarolMaljak Welcome to the forum!
I moved your post into the correct forum category, since it does not appear to be a feature request. I also cleaned up some strange text that had been inserted into your post, and changed the app: tag from app:web-vault to app: browser (since you seem to be asking about the browser extension).
After installing the browser extension (add-in), you should open the extension window (which you can do by clicking the Bitwarden shield icon, or by pressing the keyboard combination Ctrl+Shift+Y).
The first time that you do this, you will need to enter your Bitwarden username (email address) and your Bitwarden password (master password); if you have configured two-step login (which is recommended), you will also need to provide your second authentication factor (e.g., a one-time code from your email or from an authenticator app).
When you have logged in to the browser extension, click the 
Settings button in the lower right corner of the browser extension window; on the Settings page, click Account Security. On the Account Security page, find the dropdown menu that is labeled “Timeout Action”, and make sure that has been set to “Lock” (if not, please change it to “Lock”); in addition, in the dropdown menu that is labeled “Timeout”, select “On browser restart” for now (later, you should reduce this to a short time period, like 15 min, to be more secure).
While your browser extension window is open and unlocked, you can create a new vault item to store login credentials for a website account, by clicking the + New button and selecting “Login”. On the “New Login” page in the browser extension, fill out the username that you wish to use for the website, then click 
to generate a password (click Use this password when you have configured the desired password generator settings), and click the Save button. Finally, click the Fill button to transfer the information to your online account registration form.