While it is rare, it is possible.
Yes, but it is extremely rare, less than 1%.
you can buy them from the steam store, you can find it as a random drop, the items can be crafted or you can trade for them.
no, scrap and other metals are created by smelting weapons that you have.
Yes, you can receive hats from The Item Drop System.
You can find Team Fortress 2 at store.steampowered.com
You find them
You have the same chance of getting a hat in any type of map on Team Fortress 2. It's not the map that gives you items, it's the drop system that gives you up to 12 items every week, as long as you play.
Well, team fortress 2 is more of a cartoon game and you have to buy and "find" guns. Call of duty is a more realistic and better graphics. I would take call of duty over team fortress 2. But thats just me.
Yes, as long as you are in-game, you are able to find items.
not really, no.
You simply find them randomly as timed drops, you unbox them, you trade for them, or you do achievements
Well in team fortress 2 to find items on the home screen click servers, select what you want, join the server and then play :). You find items completely random by just playing, but you can only find ten a week. This resets on Thursday so if you have found ten items before Thursday, after you can find ten items again. Hope I helped :D