Fabric (And FabricAPI) are required. Please refer to their installation instructions <ahref="https://fabricmc.net">here</a> and come back once you have Fabric functioning.
Once you have fabric installed, simply download the MineLittlePony-version.jar for your particular version from [the releases page](https://github.com/MineLittlePony/MineLittlePony/releases) and place it into your mods folder next to the fabric-api jar and (optionally) the hdskins jar.
Check [releases](https://github.com/MineLittlePony/MineLittlePony/releases) for the most recent release version or the `gradle.properties` for most recent snapshot version.