Does Mac Book Air have a touch screen?

Some now-discontinued Mac notebooks had a small touch screen called a Touch Bar. This took the place of the function keys, and sometimes, of the ESC key. As on other Macs, the main screen was NOT a touch screen. The most recent Mac with a Touch Bar was the 13" M2 MacBook Pro, a notebook similar to a 13" M2 MacBook Air.

No

No Macs have touch screens.

If you use the SideCar feature of macOS, then you can use an iPad as an external screen. The iPad has touch. I've never used this, so I don't know how well it would work (probably depends on what & how you intend to do):

Use an iPad as a second display for a Mac - Apple Support