How to fix the ground texture in unity

On my Unity game when ever I try to add a texture on the terrain it comes up as a solid color instead of what the texture is. For example if i’m adding a grass texture it would ether come up with some dark color or looking like there is no ground what so ever.

Terrain is created from the Terrain - Create Terrain button and specified with Set Resolution

Painting Trees or Details can be done through the inspector-“paint texture” while terrain is selected

Details are added by selecting paint details from terrain inspector

Hope this helps you