Wordpress website has critical errors

I've updated the plugins on this website, and now there are critical errors.

I deactivated the plugins, and I'm getting the error message below. I have the login to the hosting and to the control panel.

I'd like the website restored, made compatible with the latest version of Wordpress and checked over to make sure all the tabs are working. This website was working fine until I updated the plugins, no other changes have been made. There are back-ups to the website, but the hosting account does not allow for them to be installed unless I pay extra.

I am looking for offers for this project.

Fatal error: Uncaught Error: Call to undefined function create_function() in /customers/1/5/3/southwest-digital.com/httpd.www/wp-content/themes/brandon-old/functions/theme-functions.php:781 Stack trace: #0 /customers/1/5/3/southwest-digital.com/httpd.www/wp-content/themes/brandon-old/functions.php(49): require_once() #1 /customers/1/5/3/southwest-digital.com/httpd.www/wp-settings.php(555): include('/customers/1/5/...') #2 /customers/1/5/3/southwest-digital.com/httpd.www/wp-config.php(68): require_once('/customers/1/5/...') #3 /customers/1/5/3/southwest-digital.com/httpd.www/wp-load.php(50): require_once('/customers/1/5/...') #4 /customers/1/5/3/southwest-digital.com/httpd.www/wp-admin/admin.php(34): require_once('/customers/1/5/...') #5 /customers/1/5/3/southwest-digital.com/httpd.www/wp-admin/themes.php(10): require_once('/customers/1/5/...') #6 {main} thrown in /customers/1/5/3/southwest-digital.com/httpd.www/wp-content/themes/brandon-old/functions/theme-functions.php on line 781
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