Import the Unity package through the Asset Store for older Unity versions (under Window/Asset Store) and through the Package Manager for newer Unity versions.
If you are using the Built-in Standard Pipeline, you are good to go ! You can start navigating the /Scenes folder or using the assets found inside the /Prefabs folder !
If you are using a SRP version compatible with the package, please check the next part !
To use the package with URP or HDRP :
Shaders, materials, demo scenes and some prefabs will be replaced.
<aside> 💡 Take note that the VFXs and the Demo Scenes are only supported in 7.xx SRP versions. We won’t be able to provide a lot of support for any SRP related issues as this process is still new in Unity but feel free to contact us.
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How to get the same set-up as you for the scenes ?