Low light means higher ISO and a slower shutter speed (this is what night mode does on iPhones).
In order to avoid blurriness both your camera and subject have to be really steady (very difficult for people even kids to stay still).
Taking pics of kids indoors under low light settings is difficult; digitally zoomed pics will look grainy and smeared.
Either try a Pro, switch to point and shoot camera, or add light sources for subjects (flash or another light bulb).