You need more light in the foreground- it’s extremely dark, and a strong lamp like that would be putting out a lot more ambient light
I assume you are using a photo as backdrop… that’s totally okay, but: your models seems to by not super high quality… that’s also okay… but i would make the high resolution photo… hmm 
maybe some more fog/mist outside or even rain drops on the window to take the focus away from the background… (curtains ?) maybe even make the close up bigger (meaning moveing the camera more to the car)… and the light… turn the lamp more to the window so that the viewer isn’t dazzle by it (which (s)he isn’t because the light is… unreal).
The lamp looks flat and unreal.
If you use the Eevee render engine I would enable the Bloom effect.
If you use Cycles you can get a similar glow effect in the compositor.
If you want to make it more (photo)realistic…
- use an IES profile for the Spot light (I guess you have one in the scene?). For example this one: BEGA 84693K4 2044 lm,43 W (00c6ce79e1d2cdf3a1fb491aaaa47ae0)
- add some glow and streaks to the lamp in the compositor. Shift the colors a bit if you like, for example, blueish or reddish-yellow
- add a Lens Distortion for chromatic aberrations and to mimic a photo lens
- optionally, add a Principle Volume Shader for god rays to make the light cone visible
- and for artistic reasons (as Okidoki just suggested) turn the lamp a bit because the light may distract the viewer and could disturb somewhat
Example:
- for longer streaks increase the Fade value of the Glare (Streaks) node
- for blueish light decrease the B curve and leave or increase the others slightly
- for reddish light decrease the R and the G curves and increase B, also increase C if needed to lower the size of the glow