Can you run gcode from an SD card? That’s the only way I do it. Plenty of folks on here who use a computer, though, so they might be able to help with that. I would suggest putting a gcode file on an SD card and see if you can run it from the LCD screen.
Ryan has a test file somewhere here on the website with his logo that you can try if you’re not sure if your gcode is well-formed.
I suggest you start your own thread in the getting started section – more people will see it and be able to help out. I’ll help however I can, but Ryan is really the expert – it’s his machine, after all!