As @Walter.I stated "Please describe exactly what you want to do with what " Read the 'Sticky' at the head for the main Sound Forge forum page.
That said, are you using the same email address that was used when "it" was originally registered? Where was "it" purchased? How many PCs was "it" activated on?
Assuming you have Sound Forge Pro or Audio Studio and not the 365 subscription version, most Magix software can be activated on two PCs simultaneously.
btw, welcome to the Magix Sound Forge users forum @Jen-Hernandez.