Black and white view after splitting window I have a huge problem (I'm new in blender so it maybe be something stupid actually), after splitting the windows and go back to only one view window, I can not see colors anymore. At the beginning, when splitting the window, the left window is normal (with colors if you had an object or something with a color material) and in the right window you had a black and white image. Ok, after joining the windows I only have forever and ever the black and white view :/, the only way for me to see the material's colors is to render the image. I even  tried to delete and reinstall Blender (2.8 and 2.81a) but I still the black and white view. Can someone help me with this issue?
If I'm understanding your question correctly, the issue is that you are in Solid view and want to see the Material Preview.

Click this button at the top right of the 3D viewport and you will see the material attached to the object.

 

As an aside, you can change the color of objects in Solid shading mode by scrolling down towards the bottom of the Material Properties tab and choosing a color for the object under Viewport Display.