Hey.
ad. 1
The hot-end heater has a resistance adapted to the main power supply.
So if your main power supply gives 12V then ...
ad. 2
It can be divided, but
this solution is not good. Depending on how you connect the heaters of many hot ends ...
You need to know the consequences.
Basic knowledge of electronics, how to connect resistors and how to perform calculations in this area will be useful here.
At this point I would like to draw your attention to ...
We return to the circuit diagram.
Note that each extruder connector can control the heating of the hot end.
So you don't have to divide anything because it's already done.
ad. 3
ooojjj
In this respect, my knowledge is too little, for a prosaic reason.
I do not yet know these models of printers.
Unfortunately, no description of the printer available in the web shop contains this information.
But we can ask a colleague
vert to check this information.
vert, would you like to help us