You have your start switch plugged into the clear CMOS header so the motherboard won’t start.
See Picture Below:
Ok, now the correct place to put the switch is a little lower on the 3rd and 4th pins from top left of the header as shown in the following picture, item 4 on list:
The header for this may be colored RED on those two pins.
Once you have the motherboard powered up, set the “on power failure” setting to “always on” and you won’t need to use the power switch to start under most conditions.
You are using the 4+4 pin EATX 12 volt power for the CPU, you don’t need to use the extra 4 pin socket under most conditions but the bigger socket is mandatory.
Standoffs: This motherboard only has 6 mounting holes. Only use 6 standoffs that correspond to those mounting holes…Using more will short out the motherboard.