Question Texture from shader Graph to terrain as a heightmap?

I want to get a result of blending and use it as a heightmap for a Terrain. How to make it possible?

 

I used terrain 0 times in my life, but assuming you can set any splatmap you want, you could just put quad on scene with material using your noise texture, then take a shot with ortographic camera (of this quad only as unlit) and save it as texture.

 

I tried this Camera-to-Texture hack but I got this texture affected by the directional light and it become non-black and white but sort of yellow). Ok if I forget about the terrain itself, how can I generate it then from a shader?

 

Then as I said: use unlit shader (and disable post processing volume for this camera).
I don't know terrain API, so can't help you with that, you need to check docs or tutorials on youtube - there should be plenty.