ImgBurn is powerful, but many download sites bundle adware with it. Always download from the official developer (ImgBurn.com) or use a trusted source like Ninite.
If you have purchased a license but do not yet have the registration code, follow these steps to generate it: Locate your Serial Number
Searching for an is a common internet hunt, but it is a hunt for a ghost. While you might eventually find a string of letters and numbers on a dubious forum, the odds of that code working on a modern version of Windows without infecting your machine are near zero.
Licenses are usually version-specific. If you bought a code for version 8.xx, it might not work for version 10.xx.