The Forge website has a quick guide to getting started with modding. I’m just getting back into it, so I thought I’d walk through the steps to get a project set up with Forge.
Modding
Creating a non-official addon for a released game.
Setting up a Development Environment for Forge Modding
Note: Since I have a Windows machine this tutorial will focus on that platform.
How to Learn Minecraft Modding
Learning for the sake of learning is an exercise in futility. You will often end up losing focus and will never have achieved anything. You need to set a clear goal, and then figure out how to meet that goal.