Currently I have a backend express server that is used by our mobile apps (iOS and Android). I want to use Next.js for our web app version of the same application for the benefits that its been praised for (SSR, SEO, etc). I don't want to rewrite our current backend api onto the Next.js server. I just want to use Next.js as the frontend while it sends request to our current server (ideally I want to keep the backend code in a single server). I've done a bit of digging and it's entirely possible, however will this render the benefits of Next.js useless so I might as well just use CRA?

I want to have an application that is the most SEO friendly and efficient for users. Wondering which option is the best in this case.