3D model space to 2D model space

Initially I work in 2D model space, and then, intentionally or accidentally I change the plan or the view and enter 3D model space. Allthough I return the plan to TOP or simmilar not to be in perspective than in parallel plane, I cannot return in the 2D modelling space. The problem is that my background colours go gray like in 3D model space setup and I want my colours to be in like 2D setup - for instance background is black.

I would check to make sure which workspace you are really working in. There should be an icon with a gear on it in the bottom right-hand corner of your screen.

To change the color of your background click on Tools > Options > Display tab then on the Colors button.

I'm working in 2D model and annotation or whatever it is called.

I know how colours are changed but I hope that there must be a better solution to change to 2D model space back.

I just gave you the solution (I think). Maybe I misunderstood your question.