Did I understand correctly how RAM is arranged?

Question

Programming

Did I understand correctly that:
- all computer memory is 8-bit or 1-byte cells
- a variable in my program, depending on its type or size, can occupy one or more cells
- the computer does not know the size of the variable , because see p #1. that is, whether these are 2 variables of 8 bits or one 16 bit - he does not know because both those and those are still stored in memory in the same way.
-- only we can tell this in our program by explicitly specifying the size of the variable.
Please answer yes or no and don't go deep.

Answer 1

-- Please answer yes or no and don't go deep.
as you wish
1) no
2) yes
3) yes and no
4) yes

Answer 2

Very simplistic, but in the right direction.

Answer 3

Yes. All of the above is true as long as we are talking about x86 (including x86-64).
But for other architectures, the answer may be different.