WPILib refers to a set of libraries tailor-made for FRC applications by Worcester Polytechnic Institute. WPI also releases and hosts a wealth of information and a variety of tools to help you program FRC robots. The WPILib Docs are an excellent place to learn about a lot of things FRC - from basic wiring to PID control.
NI Game Tools is a collection of programs with various different utilities to help you with your FRC robot.
This document will expose you to the most critical parts of the ecosystem, but in the effort of not being redundant with the WPILib Docs, won’t go too in-depth.
Install these tools at https://docs.wpilib.org/en/stable/docs/zero-to-robot/step-2/wpilib-setup.html and https://www.ni.com/en/support/downloads/drivers/download.frc-game-tools.html#553883.
FRC Driver Station (Game Tools)
The FRC Driver Station is a program you’ll come to be very familiar with - it connects to your robot via the radio, or Rio and gives you a variety of information about the state of your robot.