Where can i download Final Cut Studio?

FCS is not and never has been available from download from Apple .

If your OS is , say , about High Sierra or later then even with an optical drive you would be unlikely to install / run FCS applications . Some of the FCS applications may work in El Capitan , e.g. FCP and Compressor.

If you have Catalina or later then it definitely will not be possible .

As mentioned, FCS is not a download and will not run on many of the newer OS versions. If you have the right OS, you can always buy, borrow or rent an external optical drive to install FCS on your system.

-DH