I would appreciate it if there is somewhere I can get Shed Plans for a 12 > X > 16 Shed.
I don't want to be a smart ass, but stop and think.
1/2" CDX comes in 4x8 sheets. 2x4s, 2x6s, etc, come in 8',12',16' and 20 ft lengths.I built a storage shed for my tools used to build a boat that travels down the freeways at 55 MPH when it is time to find a new yard.
Double frame a 12x16 box from 2x10s for the floor system with 2x10 laterals on 2' centers.
Use 2x4s for the walls on 2' centers and 2x4s for the roof on 16" centers.
Sheath with 1/2" CDX, slop on some paint on the sides, some roll roofing on the ceiling and get on with it.
HTH