If you are trying to make money with photography, essentially what you are doing is creating a product or service as a small business. Part of that is the marketing and promotion side of things. It’s going to be really hard to catch people’s attention if you try to market 15 different aspects of your photography.
It’s sort of like talking in a crowded room. It’s so easy to blend in with the background noise, you need to find a way to really stand out to be successful.
I exclusively do low-light and no-light photos.
On a tripod: iso 100, f8, and then let the camera meter the shutter speed. That should get you in the ballpark.
Adjust your shutter speed or use exposure compensation to your increase or decrease exposure