alright I have been able to put in flight plans, but there are no STARs for the ifly 747. any help?

Yeah, I don't think the ifly comes with any SIDs/STARs to begin with. 

Most addons with FMCs require a database of some sort that contains all the SID/STAR data.  You can try searching flightsim.com or avsim.com to see if there are any databases you can download for free for the ifly.  I know PMDG and level-d quite often use subscription databases for their products.  Unfortunately, you often have to pay a small fee to get the most up-to-date ones (I believe).

If you can't find a database catered to the ifly, then you can, as EVVFCX mentioned, create them manually by first finding the charts you want to use and entering the waypoints into the leg page of your FMC.  You may have to learn how to read approach planes, however, if you don't know how to do so already.

I fly mostly the fmc equipped paywares when it comes to jetliners, and I'm typically too cheap to update the databases anyways.  Online ATC communities like VATSIM often use outdated charts anyways, so often I have to input STARs manually based on that. 

If your flying offline, you probably don't even need to bother with STARs if your using the built-in ATC, since it vectors you to and from and airport anyways.  If your not using ATC, then you can simulate a more realistic experience by either entering your own STAR into the FMC, or as said, finding a database if it exists.