How to "position" a custom code snippet?

[jPaul]

Hi Everybody,

This is just a small part of a dynamic webpage. This one is pretty common.
So, I have a javascript snippet that will compare the visitor input for Editbox1 to
the visitor input for Editbox2.
https://www.dropbox.com/scl/fi/cvxxa6tl ... 3ar9&raw=1
My problem is that I have no idea how to position the javascript snippet to trigger as the visitor is entering their password in Editbox2.
Of course, I will want to apply several different scripts (Javascript/PHP) to several visitor inputs using the same strategy. I face the same problem though, I have no idea how to manage the positioning.

Any suggestions will be gladly studied.