Fatal error after wp update

Hello ! I’m new here and I don’t know how the “support forum ” works.
Well, I don’t know If this is the right topic and If it’s not, I’m sorry.

Well, here is my problem. I uptade my website ( wordpress version) and then, I got a ” ERROR 500 “. Some topics says that it was a .maintenance problem, and that I just have to delete it. I’ve done it, and it doesn’t changed anything.
I try to delete the .htaccess but it doesnt worked neither.
I can’t have access to ” mywebsite.com/wp-admin/

when I try to go on my website, it’s written :

Fatal error: require(): Failed opening required ‘/home/u323760552/public_html/wp-includes/class-wp-post-type.php’ (include_path=’.:/opt/php-5.5/pear’) in /home/u323760552/public_html/wp-settings.php on line 160

Here is my website adress :

crespin-baptiste.esy.es

I really don’t know what to do. I hope there is a solution. Have a nice day.