Can you copy stuff from CD-R?

No. Technically, a true CD is a "read-only" media - that is, once the data has been put onto it during manufacturing, it cannot be altered.

Now, there are several types of technologies that do allow you to write data onto what looks to be a CD. CDs marked as "CD-R" or "CD+R" are referred to as "recordable" CDs. Using a special kind of CD player (typically found on a computer these days), you can write data ONCE to such a CD-R (or CD+R), but cannot erase anything already written.

Another type of technology is the CD±RW, also known as the CD Rewritable. This form of CD allows you to write multiple times (and, also erase), just like a hard drive.

Modern computer CD (or DVD) drives are mostly of the ±RW form, so most people can use a normal CD, the CD+R, the CD-R, or a CD±RW disc in them. Remember, each type of disc is different, so you must buy the disc media of the type you want to use (i.e. you can't use a CD disc as a CD-R, you must buy a disc specifically labled "CD-R")