How to take sound off when taking a picture?

Hello ~ Take a look as these:

*Disable the camera shutter sound using the Live Photo feature. Go to Settings > Camera > Preserve Settings and turn on Live Photo.

Or:

*Mute the phone's ringer. To mute… toggle the switch on the left side of the phone.

Or:

*Access Control Center and lower the volume. Swipe down from the upper-right corner of the screen and move the volume slider to zero.

~Katana-San~

If your camera was meant to be sold in Japan or Korea, you can't turn the shutter sound off. Their government mandates the sound must not be able to be turned off.

What is the model number of your phone?