How to display India country first in country selection drop down list in WordPress

You can use a code in your functions.php file to select a default country in checkout page drop-down.

/**
 * Change the default state and country on the checkout page
 */
add_filter( 'default_checkout_billing_country', 'change_default_checkout_country' );

function change_default_checkout_country() {
  return 'IN'; // country code
}

Please let me know if code works.