yes
Check on the inside of the box if you bought it, or if you pirated it, download a crack or keygen software
Yes you can install Sims 3 on a PC or a Mac.
you have to buy an external drive to attach to your PC in order to install the game.
You get it from the store or steam if they have it.
yes
The code is on the back of your manual.
Yes, you must have a serial code to install the Sims 3.
You can't. You need a serial key for The Sims 3 in order to install it.
it is
Thief...
The code to install Sims 3 is on a piece of advertising paper in the back of the disc container. The should be a code listed at the top of the paper.
to install the game, you would need to buy an external disk drive so you can run it.