Hello
I rendered a project using command prompt and I got an issue about lights!
As you see they neither has no light nor any sort of reflection! What is the problem?
Thanks for reading
If you have a problem with lights, how about showing us the light settings instead of the outliner?
No one can even start to guess, with nothing to look at!
Help us to help you…
What do you exactly mean?
I am a bit new to blender
I just know there is a setting menu for each light you add to your scene
Exactly…that would help…
Right Panel under the outliner
Object Properties > click on the light bulb… show us a couple of your light settings…
Also…Cycles or EeVee…
Though they show fine in the rendered viewport they are far too dim for a render image, especially for EeVee, and it also depends on the distance from the lights the objects are as well as their placement in the scene…
If they are also colored dark, like the last one shown, you might have to kick that one up above 100w I would also, for now, turn OFF custom distance, I don’t know your scene dimensions H/W/D to be able to say if they are in the right clipping distances…
Your world settings will also affect how the final scene is rendered… did you add a world setting, Sky, HDRI, or a lighter color?
In the drop-down for the render settings ( 4 spheres on top bar) check if the World is turned off or on…
I think I can only see Emission. Please check the Composing 
How and where should I check? :))
I looked at it closely once again, and it looks similar, but it looks different
Emit appears to be a vivid color. 
Composing is what shows or edits renderings anyway.
I don’t think I can find out without checking the .blender file to figure out the problem.
If your lights are in a different collection from your mesh objects, AND, the lights collection isn’t set to render via the checkbox in the outliner…then your lights will not affect the collection that has your mesh objects in it.
Without seeing your entire collection setup, the foregoing is what I suspect is happening.
