There will be poblems, first of all I didnt have a pendrive of 8GB so I installed the image on an Ipod, for that oyu need to put it on disk mode.
While doing that, it came to my attention some posts about NUC not recognizing drivers for Windows 2012 R2, so there are some workarounds to enable that.
And at last, activating the license was done trough the command line.
Licensing Windows 2012 r2 Virtual Machines
For licensing the Hyper-V virtual machines once the host is activated, run this commands
PS C:\Users\Administrator> dism /online /get-currentedition Deployment Image Servicing and Management tool Version: 6.3.9600.16384 Image Version: 6.3.9600.16384 Current edition is: Current Edition : ServerDatacenterEval The operation completed successfully. PS C:\Users\Administrator> dism /online /set-edition:ServerDatacenter /productkey:Y4TGP-NPTV9-HTC2H-7MGQ3-DV4TW /accepte ula