Using the edge mode from editable poly I have selected the lines where the window should be and clicked create shapes from selection. Also I changed selection filter to shapes. When I had the line I have created I coppied it twice placing one in the moddle and another at the end.
I attached all three lines and going to modify panel selected cross section.
Then, selecting created cross section on modify panel I selected surface and the window appeared.
Some front windows were made from boxes it is faster and easier.