Modern C++ Web API (Back-End Development)

I just want to know what resources I can read about on how to accomplish this with best practices and safety in mind. I know 99% of the responses are going to be "you could do it in C++ but you just woulnd't want to. use node.js or asp.net". I have experience in both of these, and they are wonderful tools. But my question is not "is it possible to do in C++" my question is "okay it is possible to do it in C++. how do i go about doing it with all the implications in mind considering C++."

This is mostly a learning experience to me as I dive deeper to further educate myself on how things work on a fundamental and low level. however i don't want to cut corners just because it's a learning experience. I'm interested as to all of what has to be considered when developing a back-end with C++, and of course the best practices to hurdle over those obstacles.

So far I have been able to use FastCGI with nginx. However it just seemed to good to be true if that was the "only" or "best" way to do it (in the modern day). however i would be curious what you as in the community have to say about FastCGI. Is it secure enough? is it safe enough? what saftey concerns are there when using FastCGI? or should i be doing it a completely different way (i.g. modules with nginx or something. or build my own webserver from scratch that gets reverse proxied by nginx?)

thanks in advance for your kind and prompt responses.