So the way around this is to start to add light to the scene. There are a few ways to do this. You can use a reflector. These are very inexpensive and very easy to use. But you often need an assistant to hold them and if the assistant is not good at being steady or seeing the light the reflector is giving off then it can be a bit frustrating. It is possible to get stands that are made to hold reflectors, or you can build a DIY stand yourself.
Both the photo at top of Phire Free and above of Marisa were shot using a single manual speedlight. I balanced the light output of the flash to go with the ambient light in the skywalk we were in. I was able to light the models just a touch more than the environment and also get them to stand out. In this case I used a voice activated light stand (someone holding the light). So the models took turns holding it. But I have an inexpensive stand I could have used also. You can see the effects of the light in the shadow from Marisa's hand in the lower photo.
With the light off camera you need to have a way to trigger the light. I use Yongnuo RF-603 wireless triggers. They are very inexpensive and have been very reliable for me. They don't do TTL, but Yongnuo does have a set of TTL wireless triggers too if you want to use TTL strobe setups.
The biggest thing I want you to take away from this is to start to think really hard about light. Where is it coming from? How can you shape or change it? Mastering light is essential for really getting great shots. It is easy to teach the mechanics of photography, how to use the camera, how to set your exposure, how to pick equipment. Learning lighting is one of the parts of photography that will take a lifetime to really learn. It is one of those soft skills like composition that is the art of photography.