Wordpress http 500 errors and Wordpress critical errors on website

I recently hired someone on freelancer to add cpanel to my Google VPS. Then transfer my wordpress website and change the domain for it. Since then I now get http 500 errors and wordpress critical errors on website. I have attached both screenshots to show you. Prior to the change in domain and transfer to cpanel. I never had this error at all. Now this error is happening often, for every 10 pages I click on, I see these errors 4 or 5 pages. It doesn't matter which pages, it randomly happens. Wordpress links to https://wordpress.org/support/article/faq-troubleshooting/ for more details, but Im not sure what is wrong. I need someone to fix this problem asap.