Keyboard and mouse won't work when first time installing OS

[vladlion12]

Firstly, my USB ports all work, as i plugged my flash drive(because i don't have a disk drive) and the mouse and the keyboard work in bios, however after quitting BIOS they don't work, but what's funny they only both have their LEDs on so it looks like the work from a distance but they dont''t. Its a completely new PC, i built it myself, and its the first time I tried to turn it on. Also, it's a windows 7 and I can't change it.

My motherboard: gigabyte b360m ds3h

Thank you for your answers

 

[popatim]

How did win7 get onto the pc?