You will want to fork this repository into your own account, then then clone that onto your local machine:
git clone https://git.blakerain.com/<your-username>/utamacraft
You will want to install a JDK. When working with Forge 1.20.1-47.2.0 you will probably want JDK 17, which can be downloaded from Adoptium:
https://adoptium.net/temurin/releases/?version=17&package=jdk
Install the Community Edition of IntelliJ:
https://www.jetbrains.com/idea/download/
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