How to make sure that two Windows on one computer do not see "foreign" hard disk partitions?

Question

Hard disks

The bottom line is, I want to roll the second Windows on my computer.
Conventionally, there is 1 hard drive and three partitions:
A- OS1 + personal files
B- personal files
C- an empty partition for installing OS2
However, as far as I remember, if two OSes are installed, both will see the contents of all partitions. I also need OS1 to see sections A and B, and OS2 only sees its installation partition C and all the files on it.
Is it possible in principle and how to pull off such a feint?

Answer 1

No, It is Immpossible.
The OS works with the computer - what is installed is available.
There are no insiders or outsiders.
You can encrypt data so that it cannot be read from another system, or use virtualization.

Answer 2

On the second OS, delete the letters from the first two volumes.

Answer 3

Winxptweaker
xptweak.sourceforge.net
Old program
But doing its job
1 deny access to the necessary partitions
2 restart
3 they will no longer be visible in the system