I notice you are running an older version of grbl so you should choose the GRBL-M3 device in LightBurn. Make sure to set the LightBurn device settings (S Max) to match your GRBL setting ($30). Ideally, you would upgrade to GRBL 1.1f and then use the GRBL device.
Here is another great resource for your setup.
As another member previously posted, “Scroll down to the bottom “operating instructions” and follow that. Once you have it working in elekscam, it should work in LightBurn. Follow the instructions to the letter and that will get you up and running…”
Additionally, there is a group for these types of machines on Facebook and quite a few people there use LightBurn, so they would be able to advise you more. https://www.facebook.com/groups/107222596696733/