How do I get to the Terrain Tools and Advance option in Package Manager in Unity?

I am not able to find the Terrain Tools option in Package Manager when I search it. I am new to Unity and that’s why I was following a tutorial. The video was about building a terrain and there he told to get the terrain tools first.

For the terrain tools we need to go: Window > Package Manager > Packages > All Packages and then search it

But in the Packages I don’t have the All packages option and also I don’t have the Advance option as told in the video. I am sure that the Unity editor in the video is of an old version. Currently I am using 2020.3.8 version of Unity.

If there are some major changes between that version(used in the video) and my version(2020.3.8) then where do I find the Terrain Tools and the Advance option?

Screenshot From My Computer – Screenshot From My Computer

[NOTE: If there are any confusions, please refer the video]