If using the zip file, extract the contents into your Minecraft versions folder, typically found in %appdata%\.minecraft\versions on Windows.
The free version of Aristois provides a comprehensive suite of tools accessible through a custom in-game interface. Aristois-Free.jar
Double-click the downloaded Aristois-Free.jar or installer file. Follow the prompts to select your desired Minecraft version and launcher (e.g., Vanilla, MultiMC, or Prism). If using the zip file, extract the contents