Where to add this code for a Modal box to work?

Hi im using WordPress and was given this code below to add to a website but unsure where I need to add it in order for it work as a Modal or if there is a plugin i can use to add this code. Any help would be greatly appreciated.

Answers:

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Method 1

Given that it is a modal, you should be able to add the code in header.php or footer.php. I would recommened adding to footer.php above wp_footer();

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