Leave that big plastic screw, that is for the wind baffle.
Easiest option is to drop entire bumper.
The plastic clips are quite brittle, you can buy a box of replacements on Amazon or eBay for under £10, i got assorted toyota set and replaced ones in engine bay, front trims etc at the same time.
A screw and a bolt on the wheel trim, about 8 plastic clips running around lower edge of bumper, and 4 bolts visible when you open boot.
Start to pull bumper from wheel arch, the are plastic lugs that i found easy to disengage using a trim tool.
Entire bumper will have a single loom connector, and you will find the fog light connector near the drivers side reversing sensor