please how do I use this alert in a php line

Answer 1

JavaScript is the default scripting language in HTML5 compliant browsers, so you don't need to define it. Just <script> will do.

Answer 2

In PHP the script is calling similar to HTML, <script src=""></script> if is external or inside the tags, if you want put information about the PHP on the get data, so... is other question.

Answer 3

so I don't need to describe the script language ?