With regards to the front pannel USB's, there will be USB headers on your motherboard, if you cant see them look in your motherboard manual. There will be a cable running from the usb slots at the front of the case that will need connecting to any of the USB headers.
With regard to the rear fans, the 261 has space for 2 x 80mm fans, and that's the biggest that will fit. Any bigger and they would interfere with the I/O ports on the motherboard.
Found the cable plugged into jusb 1 and nothing tried jusb 2 and 3 nothing is it possible its broken although it seemed fine to me