Your printer likely came with a CD. However, modern laptops and PCs no longer have CD drives. Furthermore, the drivers on a CD are often outdated by the time the product reaches your shelf. If you must use the CD, check the version number against the website to see if a newer update is available.
Downloading and installing the correct drivers for an iTech Thermal Printer Itech Thermal Printer Driver Download
Once your driver is working, keep it that way with good habits. Your printer likely came with a CD