Text editors are the tool that we use most often. There are a very large number of them out there. You probably just want to pick one that works for you and get used using it.
The most widely used ones around KIPAC are:
Emacs and the popular MacOs version Aquamacs.
Nano and the more modern version micro.
Vim and the more modern implementation Neovim.
Some other common text editors and development environments are Atom, VS Code, and Sublime Text.
Here are some posts that might help you decide which one to use:
It doesn't matter too much, though if you are just getting started you might want pick one that other folks in your group are using, to make it easier for them to help you.