I know this is a stupider question, but in the past i've read you can. I read that if you change the codec or something of the disc it can burn. Is this true? I don't have a built in DVD+RW drive and I want to put Windows on a disc (RW, so I can reburn later)
You're talking about a read-only DVD drive, the name even stands for read-only:
DVD-ROM - Digital Versatile Disk - Read Only Memory
DVD-ROM - Digital Video Disk - Read Only Memory (less common)
I can see where there would be confusion, all the drives have lasers, some lasers write to some disks, why couldn't this drive's laser write to a different type of disk? But even if you could change the disk image, or software, or the drive's firmware itself, the hardware on a read-only drive wouldn't physically be able to write to a disk, here's a brief quote from wikipedia:
The reading laser is usually not stronger than 5 mW, while the writing laser is considerably more powerful. The faster the writing speed is rated, the stronger the laser. DVD burner lasers often peak at about 100-400 mW in continuous wave (some are pulsed).
So the answer is no, you can't write / burn a disk with it. You'll need a dvd writing drive.
Alternatively, consider using a USB flash drive to make a bootable USB instead. These Q's look helpful