There is no legitimate way to obtain a "free registration key" for Embird software. Embird is a commercial product that requires a paid license for full functionality Embird Embroidery Software
If you are looking for an official guide or "paper" on how registration works, here is the factual information from the Embird Official Site Official Registration Process Paid Licensing Embird Registration Key Free
Websites claiming to offer "free registration keys," "cracks," or "keygen" files for Embird often contain: Malware and Viruses There is no legitimate way to obtain a
: Embird uses an activation system to ensure each license is used according to the EULA. The software creates a unique installation ID linked to your hardware. Embird Embroidery Software Trial Options Evaluation Version : Embird offers a limited trial version Embird Registration Key Free