When I say a argand plane , in my textbook it says the plane having a complex number assigned to each of its point. I interpreted a meaning for this statement down below , let me know if it’s correct

Second is does it mean that when I talk about a plane. It is like x and z axis is one plane , x and y axis , y and z axis . So , it has to be 2D. x,y and z axis all together can’t be an argand plane. Is this correct ?

Confusion in ordered pairs :

[![enter image description here](https://i.stack.imgur.com/bAaSc.jpg)](https://i.stack.imgur.com/bAaSc.jpg)

So , there is no squaring of numbers done here like R ^2 as written . That is my confusion.