I see lots of lightening improvements in the mods section, but all of those mods look good when your character is close to your vehicle. 20 feet away, the lights don't even shine.. it looks doll and unrealistic, when you have light reflection on walls but the actual looks don't even shine. Is that a hard thing to do ? I'm not a moder, no clue how things work

I would suggest trying one of the light enhancement mods available, like Improved LED Spotlight and Corona, Bright Lights, Not Too Bright Lights, or RadianceV.

With the way GTA works, there's no settings to change the brightness by distance, this is all calculated by the game itself. Therefore, if you want to be able to see the lights from 20 feet away, they would need to be insanely bright up-close, which is just unrealistic... You could try playing around with your PostFX settings, however it's probably just best to stick to the way all of us play it.