Baseline Camera settings - ISO 100 F11 1/125 sec

Ok, so you got some lights, you got a backdrop, you have a human standing there, you take a photo...…...and its completelyy white or completely black. You look down at your camera settings . ISO 400 f2.8 and 60th of a second. Okay, not quite where you need to be.
First thing first, you new studio lights are putting out a huge amount of light. So lets drop that ISO. Lets hit that down to 100. Less light sensitivity and you are now using flamethrowers for lights.
F-stop, the other unsung hero. 2.8 allows a ton of light in. Light is our enemy here now. Flamethrowers, remember?Start at f8 but you will probably end up around f11. While 2.8 105mm lenses are awesome for natural light, that f-stop is way to wide.
Your Camera has a flash sync speed, and its probably 250th of a second,. You can go any number under that up to 60th of a second. The amount of light you are hitting with will freeze your subject

Lit awww yeah

SO, recap, ISO 100, F11 and 1/100th of a second. This will get you started. Put that in your pipe lol