3D picture / or view / or displayed in Layout, how can I stop this, or switch off?

Welcome to AutoCAD!
That is a MVIEW viewport. You can think of it as a window looking through the "paper" of the layout, into model space.
The border of the MVIEW can be selected and then you can delete it, if you want. But it's generated automatically because usually you want it to be there.
You can double-click inside the window, which allows you to pan/zoom/rotate the 3d model if you want to show an isometric view of the part.
Double click outside the window when you are done editing. Then you can continue to draw the drawing on the layout view.
If you then go back to the model tab, you will discover that it doesn't matter how you orient the part there, it remembers the layout MVIEW position.

STF

Thank you very much! It took a while but I got it. Meanwhile I used templates from my neighbor.

Thanks Again
Bogdan