How do I print with my Macbook Air other than wirelessly?

You can connect printers via USB cable. If your printer doesn't have a USB-C cable, see the following from About USB-C on Mac - Apple Support

USB-C to USB Adapter, to connect to standard USB devices, including cameras, printers, and thumb drives. This adapter cable doesn’t connect to a power adapter. See the Apple Support article About the Apple USB-C to USB Adapter.