We regret to inform you that there is currently no theme option available to disable post navigation. Since you prefer not to disable it using CSS, the only alternative is to edit the theme code directly.
You can remove the post navigation code from the single.php file.
To assist you with this, we have created a screen recording demonstrating how to remove the post navigation code: https://www.awesomescreenshot.com/video/28373853
If you don’t want to edit the theme code
The best way to deal is to create child theme and override single.php. You can create the child theme of Education Hub Pro