@itsjuicetin I suggest you have a look at this: https://github.com/Duet3D/DuetSoftwareFramework/wiki/SBC-Setup-Guide#troubleshooting The UI should display a reason why the main control application (DCS) could not be started. That info can be obtained from the logs, too.
Can you confirm that there is no microSD card in the Duet? Also, if you have a v1.02 MB6HC, you should have RRF v3.4.4+1 or newer installed. Older firmware versions with this board revision have a bug affecting SBC communication.