Latest update crashed my site

I did the latest wordpress update and it completely crashed my site. My (ecommerce) gallery was not showing and when attemtping to log in I had an error 500 to do with my image.php file. I was speaking with my hosting provider and they recommended I replace the image.php file, which I did.

Then I got this error.

Fatal error: Uncaught Error: Call to undefined method WP_Screen::is_block_editor() in /home/u411700110/public_html/wp-includes/script-loader.php:2385 Stack trace: #0 /home/u411700110/public_html/wp-includes/class-wp-hook.php(286): wp_common_block_scripts_and_styles(‘index.php’) #1 /home/u411700110/public_html/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array) #2 /home/u411700110/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /home/u411700110/public_html/wp-admin/admin-header.php(97): do_action(‘admin_enqueue_s…’, ‘index.php’) #4 /home/u411700110/public_html/wp-admin/index.php(100): include(‘/home/u41170011…’) #5 {main} thrown in /home/u411700110/public_html/wp-includes/script-loader.php on line 2385

I replaced the class-wp-hook file and script-loader with the latest versions downloaded from www.ads-software.com but I am still getting the same error, after clearing cache multiple times. I am not very savvy with these sort of things and need some help to get my site back. Can anyone help?

Stevan

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