how can i set a custom header with javascript or php? [closed]

How can i set a custom header using javascript or php? I am trying to add a custom header to my html form but i’m new to programming so i’m still learning.

I’d like to add a custom header to my form and my current form code is this one:

<form> [set-custom-header] <input type="text" name="username" value=""> <input type="text" name="setterId" value=""> <input type="submit" value="send"> </form> 

I’d like to set a custom header on that form, what could i use? Is it possible to do that without using xhr?

Thanks,