Since you want to do this with HTML, this will require some Javascript as well. I rather suspect that somthing like

<select id="country" onchange="changestatelist()">
....

<script>
function changestatelist() {
...

[download]

will be involved.

w3schools has a tutorial.

What it boils down to: If you make a website, you'll need to learn HTML, Javescript and CSS in addition to your backend language (perl, php, python or nodejs).

Edit: As a sidenote, especially for my friends in th USA: Not all countries have states or regions, especially the smaller ones. Monaco and Liechtenstein are small enough for a single postal worker to know all the adresses. And is Sealand ever gets recognized, you can tour the whole country in about 15 minutes flat.

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In reply to Re^2: how to make dependent drop down in perl script by cavac
in thread how to make dependent drop down in perl script by Anonymous Monk

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