To create a Forge mod, you'll need to install the JDK and an IDE (ForgeGradle supports Eclipse and IntelliJ IDEA) and then follow these instructions. If you're using IDEA, cpw has a slightly better set up video linked below:
Be warned that you can't immediately develop a fully functional mod with no prior experience. You must learn Java and OO programming in general before learning the Minecraft/Forge code base and how to develop specific features.
Please don't PM me to ask for help or to join your mod development team. Asking your question in a public thread preserves it for people who are having the same problem in the future. I'm not interested in developing mods with people.