I code mostly in Python, so I just read the Python documentation. And docs for whatever external modules I might be using.
Other than that, if I'm stuck and need to look at examples or the sort, Googling usually leads me to Stack Overflow.
For tools and stuff:
Sublime Text 3: Editor (Doubles as an IDE with the right plugins, and is way faster than any other JS based editor or IDE)
Git: Version control
Gitlab: Hosting code. Private repos are free.
KeepassXC: Secure password management, because reusing passwords automatically spells your doom, and remembering upwards of 400 passwords is like trying to remember what keys look like instead of just having them on a keychain.
I run linux, so most of everything else I use is platform specific and might not be of much help to the majority.