R720 come with iDRAC express by default. You can refer below link for details on various iDRAC licensing options [URL]#iDRAC-Licensing 
Hello, I was wondering if i could possibly install/add iDrac8 onto a R720 rack server.. Sorry if its a stupid question, though if not, where would I be able to get an enterprise key to access all the features?
R720 iDrac8