Use Woocommerce's email function and templates to send e-mails

woocommerce.emails.php

<?php
function my_email_function($email, $header, $content) {
  // We'll use Woocommerce e-mail function to send e-mail to users
  ob_start();

  // Get WC e-mail header
  do_action( 'woocommerce_email_header', $header, $email );
    // Content
    echo $content;

  // Get WC e-mail footer
  do_action( 'woocommerce_email_footer', $email );

  // Get output
  $output = ob_get_contents();
  ob_end_clean();

  // Send e-mail
  wc_mail( $email, $header, $output, $headers = "Content-Type: text/htmlrn", $attachments = "" );
}

// Usage
my_email_function('[email protected]', 'Your text in header', 'Your text in content. <a href="/my-account/">Click here</a>.');