I have copied all my music files (from my pc) into Finder music folder on my new Mac Pro. To get these into iTunes do I just highlight and drop these into my iTunes library or will that create unnecessary duplication?

I have copied music files from my PC into my Music Finder folder in my new Mac Pro. I want to now get going on my iTunes and want to know if I need to highlight and drag the music files in Finder across to my iTunes library or will that create additional and unnecessary duplication? I assume it's a simple highlight and drag across but just want to check before I do it. Thanks for any help.