how do i download and activate my creative suite on my mac if i already did it on my pc

If it is a Creative Suite that is licensed for a PC then it is not licensed to run on Mac - you need a Mac version and licensing to go with it.  In any case, you can not run the same suite on both platforms.  If it happens to be CS6 then you can swap for the Mac platform version but that will require giving up the PC version.

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