In the construction you have used, you should say "eighty hour", not "eighty hours". You could also say "a course of eighty hours duration in....".
I have changed "80" to "eighty". AP style allows 80 in numbers, MLA style prefers it to be written out. I suggest you follow MLA style as, generally speaking, it is more academic than AP, which therefore means is suits your context more.
I have also corrected your use of capital letters, which is something you might wish to review - you don't seem to have misused them in your question to us, so why did you use so many in the certificate?
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