Thank you very much guys!

Now its almost clear for me.
But its little bit hard any way, because I came from hipoly polygon modeling like this https://www.artstation.com/artwork/dGVOx
Moi3d is so great to do some stuff in free time or on trip on windows tablet ( best 3d app for tablet! )

Michael Thank you very much!
But I can't replicate what you gave )) After join+rebuild I got 1 single separate curve. The doing extrude and got 1 face, but dont understand how to "weld" it to the shape that I have.
I'm looking some video tutorials, maybe I missed something.