Key needs to be programed to the ECU. You didnt say anything about it being programed to that! Doesnt matter if you used the same key and ignition from the new stuff you bought if you used the origional ECU from youre car!
If you used a different ECU and it came from the car in which the new harness came from, I still suggest checking that it is properly programed to it.
BTW, at 22 I was already a Subaru Master tech (im 29 now and still doing it)..... Ive been turning wrenches since i was 7 years old. Built my first Blown small block Chevy Engine when i was 13. Dont discredit people that fast. You dont want people assuming you that you were probably some Base camp hero in the Military who sat behind a TV screen calling him self a War vet now would you? No you wouldnt.