Password protect custom template

Hello guys I’m new to WordPress and I’m having some issues. I’m making a custom theme and I need one of my pages to be password protected. I’ve read WordPress codex on the subject and all the threads I found here but none of them helped me.
I’ve made custom template that I use for my page.

My custom template is mostly hard coded and doesn’t have the_content.
This is my custom template https://jsbin.com/qayeso/edit?html

When I add password to a page using this template nothing happens. After reading stuff online I had the following idea.
I made another template and wanted to call my old template into it for password.
This is the code:

<?php /* Template Name: PwProtect */ ?>

<?php
    global $post;

    if ( ! post_password_required( $post ) ) {
          // Your custom code should here
        echo get_testPage();

    }else{
        // we will show password form here
        echo get_the_password_form();
    }

?>

But when I try this I get the following error:

Fatal error: Call to undefined function get_testPage() in
C:\wamp\www\fresenius\wp-content\themes\fresenius\indiPartnership.php
on line 8

Is there a way to make this work ? Can I make my whole custom template password protected.

Okay so I made it work with include this is my updated code:

<?php /* Template Name: pw-protect */ ?>

<?php
    global $post;
    get_header();

    if ( ! post_password_required( $post ) ) {
          // Your custom code should here
        include('indiPartnership.php');


    }else{
        // we will show password form here
        echo get_the_password_form();
    }

?>