How to get the inputs from a login page

Answer 1

Use javascript

Answer 2

In JavaScript (on the client’s side): set an id to the input tags, then to get the value, use document.getElementById("ID_OF_INPUT_TAG").value
In PHP (on ths server side, for a real login): https://www.sololearn.com/learn/PHP/1841/ and https://www.sololearn.com/learn/PHP/1840/