Given its niche utility in the healthcare sector, 7Edit is commercial software. Like many professional software tools, it operates on a licensing model to generate revenue for development, support, and maintenance. A "license key" is the mechanism used to unlock the full functionality of the software.
The internet is full of websites promising a free "7edit License Key." Nearly all of them are traps designed to infect your computer, steal your data, or waste your time. 7edit License Key