I have installed radeon pro render and when I want to use a material it doesn't work.
It is not in the material outlet panel.
and radeon pro render is well installed. Thank you in advance for your help.
"Normally, different colors or patterns on an object are achieved by adding textures to your materials."
Even though is a manual for blender 2.79, i think that what i have quoted applies on all Blender versions. You already have more that 1 material on the same object. You can only use one. If you want to modify it you have to do it with textures or images.
If you really need to add multiple materials on the same object watch the following video: https://www.youtube.com/watch?v=ms89wP8m4ZU