Make sure you've got the correct radio firmware for what you're trying to do. The NX-1300 is either Analog, Analog + DMR, or Analog + NXDN.
There's a process to go through in order to allow Wideband to be enabled. I have not yet used the Kenwood NX-1300 on GMRS, but I believe that the standard License will be Narrowband only. Once you have purchased the Key, you will need to Authenticate the software on the exact PC that you plan to use. However, you can't use the software until you purchase a $100+ License Key which will be specific to a single PC. You need to use the Kenwood KPG-D6NK software, which should be a free download. You cannot use Chirp for programming an NX-1300.