492020 Automatic form fill in

Hello, We are in need of a way to automatically fill in a form field with a username and a password from a link. For example, on a page we will have a link that says "click here to log in". Once the user clicks the link a login form should appear in an IFrame with the Username and Password already filled in. We are not talking about <input type="test" id="_wpnonce" name="_wpnonce" value=" something " /> we would like for the link to somehow fill in the information. The information will always be the same (only one user) and only accessible through the link. The link could be something like [login to view URL] Your code must be very clean, and intuitive. You also may NOT brand nor link back to you, any server or anyone else in any way. We will put the budget in escrow and will only release 1/2 after we see a fully working example from YOUR Server and the remaining will be released only after all of the issues have been resolved and you send us the final files. Thank you and we look forward to your bid