Greetings cmseth,
Your PowerShot SX740 HS camera can be used in a silent mode by enabling the Muted setting in the yellow Setup menu (Wrench icon), which silences the shutter, start-up, and operation sounds. Please note that since this model uses a leaf shutter mechanism to control exposure and prevent light leakage during the sensor's readout process, you may still hear a very faint physical click even when the electronic beeps are turned off but it is significantly quieter than the "clack" found in larger DSLR cameras.
You may refer to page 100 of the user guide for more information:
https://gdlp01.c-wss.com/gds/1/0300031221/05/pssx740hs-cu4-en.pdf
