I know this is a very broad question that allows many opinionated answers. To give some context as to why I am asking this:
I am a junior developer with 3 years of experience. My main line of work is programming ERP-Systems, so no web dev at all. In the next 2 weeks I will quit my job to join a startup owned by a friend of mine. I will be the only developer starting out, so I will have a lot of decisions to make.
In my time off, I learned a lot about how to build full stack apps. But none of them were production grade apps with security considerations, auth and so on...
My new job will require me to rebuild the frontend of the current system and later on decouple the API from wordpress to have a independent application.
I try to prepare for that role as much and as good as I can. This job creates many risks for me and I want to succeed and do it right.
Currently I am learning about auth, route guards, general deployment with Nginx, HTTPS, general system design and so on.
This is where my question comes into play.
I can not seem to find good guidance regarding on how to actually deploy a production grade web app. Full stack courses often disregard security concerns to simplify the code. Deployment often just uses some 3rd party vendor that does the heavy lifting for you. I have no mentor to ask about all of this, no guidance if I am doing right. So by asking this questions I am hoping for general guidelines on what to look out for. Maybe resources that help me with specifics.