Nothing is included in the Templates Manager at first. You will need to import the Starter Templates. For more details, please visit our Template Manager Documentation
Regarding your columns issue, it is best that you open a separate thread for this as mixing topics in a single thread would be confusion in case the discussions get longer.
Whether you choose to continue in this thread or create a new topic, please give us a screen recording of the issue so we could see what you are actually experiencing. And, open the browser developer tools by pressing F12 and take a screenshot of it and post it here.
For the meantime, please also try the following potential solutions:
Ensure everything is up to date according to our version compatibility list at https://theme.co/apex/forum/t/troubleshooting-version-compatibility/195. Please follow the best practices when updating your theme and plugins. See https://theme.co/apex/forum/t/setup-updating-your-themes-and-plugins/62 for more details.
If you’re using a caching plugin, clear all caches including browser cache then deactivate your caching plugin and other optimization plugins.
If you’re using a CDN, please clear the CDN’s cache and disable optimization services.
Test for a plugin conflict. You can do this by deactivating all third party plugins, and seeing if the problem remains. If it’s fixed, you’ll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
Contact your host to increase your allocated memory or do it yourself by adding this code in your wp-config.php
define( 'WP_MEMORY_LIMIT', '256M' );
define( 'WP_MAX_MEMORY_LIMIT', '512M' );