The Terrain Tools package helps improve the workflow for creating Terrain in Unity. It includes a number of brand new sculpting Brushes, and a collection of terrain tools in a new Terrain Toolbox to help automate terrain workflows.
To install this package, follow the instructions in the package manual https://docs.unity3d.com/Packages/com.unity.terrain-tools@latest/manual/index.html.
Terrain Tools Manual can be found here <https://docs.unity3d.com/Packages/com.unity.terrain-tools@latest/manual/index.html
Terrain Tools is compatible with Unity Editor 2021.2 and later.