If you create HTML off your home page first than this is easy for you
First Create a file Like this "template-home.php" in your theme.
Now in "template-home.php" First you must write these lines at the top of the page
<?php
/* ==========
Template Name: Home
========== */
?>
After that add your header.php and footer.php like this:
<?php get_header(); ?>
// Your Content is here
<?php get_footer(); ?>
Now your Whole HTML is work between in Header and Footer
Then Go to your Admin Panel
Go to Pages > add new
and create a page named "Home"
NOTE: When you create a page Please Select a Template of Home and "Publish" it.
Then go to Settings > Reading and select "A static page (select below)" radio button, then a drop down is active and select your "Home" Page Then click on save changes.
I hope this will help you