Set mouse to perform two clicks instead of one when the alt key is pressed

I would like to set my mouse in Ubuntu (on Wayland if possible) to perform two clicks instead of one single click when the alt-key is pressed. The problem is that I absolutely don't know how to set something similar...

Could you give me a clue ? Is that possible ?

I am not afraid of modifying system files on my computer.

Thank you a lot,

Johannes