Can a good flash make up for the small aperture of the lens?

The large aperture of the lens has two advantages. One is that you can get faster shutter speed in dark light. The advantage is that it is easier to get a safe shutter speed under the same iso, and the shooting is worthwhile. The second is that it is easier to get a blurred background.

Adding a flash can fill the light, illuminate the subject and easily obtain a safe shutter speed. Therefore, the problem of slow shutter speed of small aperture lens under dark light condition is simply solved. But the problem of blurred background can't be remedied.

If you are a news photographer, or a photographer visiting here, you just shoot for the sake of taking pictures, and you don't need beauty, just shoot clearly. Then you can look at the function of the flash described in my text above. In fact, flash can also be used creatively. In addition, if the flash is used well, it can get natural light and bring surprises to the photos. But if the effect is not good, it may also ruin a photo. It all depends on the technology of using light.