Request VPS recommendation based on traffic


I am looking for VPS RAM / CPU recommendations for a website using a bandwidth of 2 TB per month, monthly views of 694,484 and up to 90 concurrent users. It was said that I needed an extra processor on my VPS server to correct the frequent Backend Fetch Failed errors and the inability to access WordPress for them. updates. The duplicator plug-in also returns an error of failure of the extraction by the backend. I do not think this is the right solution because it happens even with low traffic, but I would like to make sure. I use Varnish, Apache, Ngnix with Centos and CWP.

May I have a recommendation, if possible? If not, what do you need more, or how can I determine how much resources I need to buy to start over?

Thank you very much!