Facing problem to implement SSL redirect

I want to add a checkbox button for automatically redirect to HTTPS if SSL is present. the process I added like below:

this is form area:

<form action="options.php" method="POST" id="<?php echo esc_attr( $  data['slug'] ); ?>_options">             <?php settings_fields( $  data['slug'] ); ?>             <?php $  this->render_form_sections(); ?>             <?php $  this->render_hidden_fields(); ?>             <input type="submit" class="wpr-button" id="wpr-options-submit" value="<?php echo esc_attr( $  data['btn_submit_text'] ); ?>"> </form>          

added new field in the form:

$  this->settings->add_settings_fields(         [                          'ssl_redirect'       => [                 'type'              => 'checkbox',                 'label'             => __( 'Enable SSL Redirect', 'rocket' ),                 'section'           => 'enable_ssl_section',                 'page'              => 'hub',                 'default'           => 0,                 'sanitize_callback' => 'sanitize_checkbox',             ], 

added this:

if ( $  wp_rocket_requirement_checks->check() ) {      require WP_ROCKET_INC_PATH . 'main.php';     require WP_ROCKET_INC_PATH . 'custom.php';   } 

this custom.php is added for making action function after checkbox is true state. this is my custom.php

<?PHP   defined( 'ABSPATH' ) || exit;    ?> 

I want to add this function code in cutom.php how to add this and how form action will perform please solve this.

function enable_ssl_redirect() {     if ( isset( $  _SERVER['HTTPS'] ) ) {         if ( 'on' === strtolower( $  _SERVER['HTTPS'] && strpos( home_url(), 'https' ) == false ) ) {         wp_redirect(str_replace( 'http', 'https', home_url() ));     }      if ( '1' == $  _SERVER['HTTPS'] ) {         wp_redirect(home_url());     } } elseif ( isset( $  _SERVER['SERVER_PORT'] ) && ( '443' == $  _SERVER['SERVER_PORT'] ) ) {      wp_redirect(home_url()); }  return false; }