This is such a vital part of the build process for D8/9 that it's a shame it's not something you just tick in the CMS. Then again, I believe the idea is to have the additional settings/files on your local machine and not on your production server. That way the production server is always fully cached and your development environment always has caching turned off. Which does make a lot of sense.

However, I tried several sets of instructions that didn't work and eventually found this: Drupal 8 Caching: https://www.drupal.org/forum/support/post-installation/2015-10-31/disabling-the-render-cache#comment-10728554

Here are the instructions found in the above link:

1 - Uncomment the following lines in sites/default/settings.php:

if (file_exists(__DIR__ . '/settings.local.php')) {
  include __DIR__ . '/settings.local.php';
}

2 - Copy sites/example.settings.local.php to sites/default/settings.local.php

3 - Copy sites/development.services.yml to sites/default/development.services.yml

4 - Clear cache

5 - Uncomment the following two lines in sites/default/settings.local.php

$settings['cache']['bins']['render'] = 'cache.backend.null';
$settings['cache']['bins']['dynamic_page_cache'] = 'cache.backend.null';

6 - Clear cache

7 - Done!