Macbook Air and iPad pro sidecar/second screen

Hi friends,

I have MacBook air A1466 and iPad pro 1670 (both older generations) on both i have the latest OS running smoothly.

I was reading the past few days and researching a lot if it's possible to use my big iPad as a second screen.

some places it says that my mac is 'too old' and maybe i can over ride it with this code.

i tried it in the terminal:

defaults write http://com.apple.sidecar.display allowAllDevices -bool YES

no change, still can't see sidecar on my Mac.

tried all the solutions given online:

https://www.howtoisolve.com/why-sidecar-not-working-with-my-mac-lets-see-sidecar-compatible-macbook-pro-macbook-air/

nothing works. maybe i refuse to accept that my mac is too old for this option :|

i find it funny that I am able to air screen my Mac on my LG TV but can't do it on my iPad

any tips or solutions?