Personally when I get a new AR I just wipe down the chamber and BCG with a microfiber clothe and then apply oil to BCG and Chamber. I like metal on metal to be separated by oil, probably just something I do from mechanic/car work. I don’t like metal on metal moving parts. Personally don’t clean the barrel on a new rifle, it can’t hurt though.

Usually AR’s seem to come with this new factory oil on everything. I don’t know what it is but it smells the same even when I buy AR’s from different manufactures. I guess its some anti corrosion/rust type lubricant.

Ultimately it’d be fine right out of the box.

As some others have suggested i’d pop open that Colt owners manual and take some time to read their directions on cleaning the rifle. Some manuals suggest breaking down entire BCG for cleaning but I find this to be a bit much for moderate range use, hell, what do I know though. I think thorough cleaning is best done at higher round counts, 500, 1000, etc, I don’t know though