you need to go through the usual steps to find the problem
I think the most important are:
- Disable Plugins
Can you log into wp-admin or is that a white screen too? If you can log in go and deactivate all your plugins and refresh the home page – can you see your content?
If so you’ve got a plugin clash – reactivate your plugins one at a time and see when the content stops working.
If you can’t log into wp-admin, use FTP to change the name of the plugins folder – change it to “no_plugins”. Now refresh the site? Does your content show (albeit messily)?
- Try a default theme
Change the site theme to one of the default WordPress themes, e.g. twentyseventeen. Does it work now? If it does then there’s a problem within your theme and we’ll need to do more diagnosing.
- wp-config.php debugging
Open your wp-config.php file and look for
define('WP_DEBUG', false);
replace it with
error_reporting(E_ALL); ini_set('display_errors', 1);
define( 'WP_DEBUG', true);
And reload your site – do you get an error message?
Sorry that this post only helps you to diagnose and not fix your site, but one step at a time.