This means you need to crank your ISO down to the lowest setting (ISO 32-64 on my Nikon D850), set your aperture to your desired depth of field (smaller apertures help lower exposure), and finally, set your shutter speed to the fastest setting that still allows you to sync to strobes (more on that in a bit). The basic formula for this is we need to underexpose our ambient light a lot and make it look like nighttime.
This "faking the night" technique works hand in hand with some specific gear you are going to need, so I'm going to talk about it all in one section.
You also aren't constrained by a tiny window of perfect light that only lasts less than an hour. If you can create a night-looking image but shoot it earlier in the day, you can also retain a lot more highlights and shadows in your dark background. Many photographers combat this by shooting during the "blue hour" or the last 30-60 minutes of visible daylight so that there is still some slight detail in the shadows. In many cases, if you take a photo at night, your background will be completely black with absolutely no detail. The third reason you might want to create images that look like they were shot at night but actually were captured during the day has to do will fill light. Taking dark images is fun and offers a completely different narrative to your story than those bright and airy shots we are accustomed to seeing. The second reason you might want your images to look like they were taken at night is simply that nighttime photos are cool and add a bit of mystery. You have to decide: do I want daylight-looking images, or do I want dramatic nighttime-looking images? With this technique, you can do both. Your subject is on a time crunch and you can't spend the whole afternoon with them capturing photos. The most obvious reason is you have a time constraint. There are many reasons you might want to make your images look like they were taken at night instead of during the day. This image was actually shot in bright daylight