There's probably a language barrier. I am assuming you are asking the following:
"I have an installer from a vendor that was built using Inno Setup. The installer requires a serial number for installation, and I want to know if I can specify the serial number as a parameter on the installer's command line so I can install the package silently."
The answer to this question is "ask the author of that installer." Inno Setup does not natively support a /SERIAL command line parameter (see the documentation[1]), but the author of the installer may have added this as a custom parameter in their own installer. (We can't answer that here as we don't have that installer's source code.)
Aside from that, this forum is for people who are writing Inno Setup installers. (It's not a support forum for vendor installers that happen to be written using Inno Setup.)