Yes, the board supports 3rd Generation Intel Core i7-37xx series processors. However, ensure your Power Supply Unit (PSU) can handle the increased TDP, as many OEM units are rated for only 250W–300W.
No. It is an internal wireless module (M.2 or half-mini PCIe card). It is not a USB dongle. pegatron 2ad5 manual link
If you are locked out of the BIOS or the system won't POST after a hardware change, locate the CLR_CMOS jumper. Move the jumper from pins 1-2 to pins 2-3 for ten seconds, then return it to the original position. Yes, the board supports 3rd Generation Intel Core