An OP can click report on their first post and ask a mod to change the title or close the thread.
It's almost impossible to get new repliers to read the whole thread before responding,
common but frustrating part of forums.
I built this same shed on a wooden foundation.
4x4" posts down into the ground(frost heave here), 2x8" joists and 3/4" floor sheathing....all pressure treated. I also added a large double door with a ramp to drive a snowmobile inside. The door was framed in wood and sheathed in the metal siding...
Just add the gravel under the blocks, no need to mortar them with one or two courses.
Definitely do the aprons as they can dig under the blocks.
Bedding inside the coop doesn't need to be sand.