This photo shows the double stud wall. The 10-inch-deep wall cavity will later be insulated with cellulose.
framing a window in a shed - Google Search
stud wall nomenclature
Common Drywall Installation Mistakes and How to Avoid Them | The Family Handyman
Advanced framing techniques using 2x6 lumber @ 24 inch spacing.
Add insulation, acoustical caulk and an extra layer of drywall
Parts of a wall frame, showing headers
Learn how to frame window and door rough openings. Learning the basic layout of a framed wall will aid in your next framing project.