New to making datapacks, could use a few pointers

Hello! We have been asking around for help with this kinda thing due to having several ideas on what to do, and we were directed here. We want our first project to either be a gun system (so we learn raycasting very early on), or custom armors that you can insert things like plates or padding into. But first, we'd like to know what programs we will need, useful mindsets to take, et certra. Thanks in advance to everyone who helps!