There are different ways to do a night scene.
Here are some methods (and surely there are more), hope it will help you.
All the pictures rendered at 1080px - 10k iterations in an average of 5mn (but I have a laptop with a 4080 12Gb).
First, the HDRI.
You can use a
HDRI only or add a
Point Light to simulate street light.
HDRI Only.................................................................................HDRI + Point Light
View attachment 4939365
View attachment 4939367
Second, the infamous
Day for Night, with or without
Point/Spot/Ghost/Emissive Light (your choice). Can be useful but tbh I think it's a tad unnatural.
For this technique, you have to set a
HDRI or
Sun-Sky daylight and, in
Tone Mapping, put a yellow/orange-ish color in the
White Point setting then tweak the
Exposure/Shutter Speed/F-stop as you like.
Day For Night.................................................................................Day For Night + Point Light
View attachment 4939390
View attachment 4939393
Third, you also can do what
Cake Slayer 3D already told you, the
Sun-Sky.
If you want to use this method and still add an additional light, you have to use
Dome and Scene and get rid of the
Environment map.
Sun-Sky with Point Light
View attachment 4939416
And last but not least, you can go all the way and use HDRI-GhostLights-Emissive Lights and Spot Lights (I know it's scary

) like I did in this pic. But believe me, you will need alot of VRAM.
View attachment 4939426
And voilà, I hope this long, long post will be useful and not too boring. If you want more explanations -> DM.