cable to connect macbook air to cannon s100

If your camera has a cable with a USB connector for the end that attaches to the computer and if your MacBook Air is a newer model with USB-C ports, use the following adapter: USB-C to USB Adapter - Apple

Or you can get a USB (C) card reader and take your card out of the camera and plug it into the Mac using the reader.

https://www.amazon.com/usb-c-card-reader/s?k=usb+c+card+reader