To be honest, id recommend dont starve together or borderlands, but since you're looking for free coop games best way for you and your friend to find them is to search "free coop games" by tags on steam
If you're laptop doesnt meet requirements or barely does it speaks for itself, you can try tweaking some config files or in game settings, other then that you're pretty much out of options.
Its called carding, and it has active forums, peoples credit card info get stolen and spread like wildfire, knew few people who did this type of crap. Their accounts get steam alert because of it. Be careful
On Dec. 1st you will have 24 hours to confirm that you want to be part of this and select a gift you recipient will get. If your secret Santa does the same, you will receive their gift on Christmas and you can open it on that day or after.
Dont take me for word tho, its been like this last year so i suppose it will stay same
Trading isnt what it used to be, try getting hats that are popular and on "high demand". As for profiting, its usually 1x scrap/rec/ref, you wont profit crazy at start, noone did.
Take it slow and be patient