I’ll echo others here by saying an 8 week old chicken won’t give you much meat... but if you really can’t house him, it’s better than him living unhappily or cramped.
For an immature chicken, soup/stock/broth would be the best use for him and make him easy to clean. Unless you’re roasting a whole bird to eat, you don’t need to keep the skin on... so you save a considerable amount of time.
Just cut off the head, skin him(once cut, the skin will just peel/tear off by hand), and scoop all the guts. May be worth finding the liver, kidneys, heart, and gizzard, if you eat those. They are very mild in chickens. If you don’t want to process the feet, just cut them off at the joint. The whole thing shouldn’t take more than 10 minutes once he’s dead, even if you’ve never done it before.