What is the correct order of photography? Is it adjusted by yourself or by the camera after metering?

If M-range is used, the shutter and aperture can be determined according to the measured values.

If it is a gear position, adjust the shutter speed after metering, but be sure to control the shutter speed. If the shutter is slow, the photo will be blurred. You can consider using lights or reflectors to fill the light, or improve the ISO value.

If it is shutter priority, then adjust the aperture value according to the photometric value, which are all corresponding.

Remember, when taking a portrait, the photometric point measures the light on the face. If you want to have other effects (low-key films or high-key films), you need to use them flexibly. No matter what file you use, how to adjust it and what effect you want, the ultimate goal is to take good photos. Take more photos and practice more, and you will naturally know how to use it.