write onto macbook screen

Hi! Just a question out of nowhere.

Is it possible in the future to have the possibility to hand write something directly onto a macbook screen?

One simple example case:

I open a pdf file on my macbook. The file needs me to sign at the end. I use my future macbook to do it directly on my mac.

As of now:

I open the pdf file on my macbook. Airdrop it to my iPad. Sign with Apple pencil. Airdrop back to macbook.

The process now is still time and effort consuming. And btw, I often have trouble with finding my device when Airdropping either from my macbook or to my macbook.

Sincerely,

Shuang