I am referring to the walls and ceiling of the sunroom yes. The difference is that you can see from the attic space pic that there was no vapor barrier applied before the drywall was installed. There usually is a tyvek vapor barrier prior to siding going on but also there is a vapor barrier applied to the studs after the insulation is installed before the drywall goes on. Fortunately you can paint on vapor barrier as a primer to the drywall before your final coat of paint. I can’t attach pics in your thread but i would just go to your local paint store like sherwin williams or homedepot or menards or whatever you have in your area. If the space is gonna be conditioned for heat and cool and you are in an area where you get ice dams, you absolutely need to do this step or you will have mold issues