how to get freeform app on mac air 2017

Freeform is included with and requires macOS Ventura. Unfortunately a 2017 MacBook Air cannot be upgraded to that. See the following from Identify your MacBook Air model - Apple Support

MacBook Air (13-inch, 2017)

Model Identifier: MacBookAir7,2

Part Numbers: MQD32xx/A, MQD42xx/A, MQD52xx/A

Newest compatible operating system: macOS Monterey

kasx92 wrote:

Why is that?

In order to use Freeform, your Mac needs to be running macOS Ventura. Unfortunately, your Mac isn't compatible with macOS Ventura.

macOS Ventura is compatible with these computers - Apple Support

Jack

That’s not going to happen.

Because it’s not. That machine doesn’t have the necessary hardware to run Ventura, which is required in order to use the Freeform app.