adapters

Thunderbolt 3 is fully compatible with USB-C, so any USB-C adapter will work for either USB-A or HDMI.

Apple makes them (but so do 3rd parties).

https://www.apple.com/shop/product/MJ1M2AM/A/usb-c-to-usb-adapter

This one outputs to both HDMI and USB-A:

https://www.apple.com/shop/product/MUF82AM/A/usb-c-digital-av-multiport-adapter

Assuming its a recent MacBook Air yes, the 2 ports on the side are Thunderbolt 3 shaped like USB-C.

So you would need a USB-C to whatever adapter.

Something like: USB-C Digital AV Multiport Adapter - Apple

There are also several USB-C docks around: https://www.amazon.com/thunderbolt-3-dock/s?k=thunderbolt+3+dock

Note that not all USB-C/TB3 docks 'play nice' with Macs. Notably, OWC and Elgato docks do, but CalDigit docks do not.