industrial building using staad.pro

I want to analyse a steel industrial building where the structure have purlin and the wall
like metal sheet or brick.
I model the structure using frame 3d model because they also have concrete floor (storey)
between 2 column (middle two column). The beam of floor also using steel too that connected
with Wide Flange beam between 2 portal with 6 m length.
If I model with open frame, many member design are fail because they have no retraint to the
direction of wall.
I make the purlin and release them at the end of purlin member so it only take moment and

they are oke.

That I want to ask :

1. How can I model using STAAD.pro the column with wall so the member can't be fail again
but my model is 3d open frame model without adding shell element for the wall?

2. Can it also model without purlin so the rafter also in open frame but it restraint to the
direction of purlin and the member are not fail too?

3. How can I restraint of floor beam because if they have no restraint, many member are
fail?

I hope I can get helping explanation, thanks a lot.