Upcast: Accessing base class methods with different access modifiers from derived class after Upcast?

Question

OOP

Hello. I don't know how to insert the code, but here's an example question:
There is a base class with valid methods:
class X
{... fields/properties...
public int Aaa();
protected int Bbb();
private int Ccc();
...}
And there is a child class in which the upcast is made (also a couple of methods for example):
class Y : X
{... fields/properties...
public string Sss();
protected string www();
private string Ttt();
...
Y petya = new Y();
X man = petya; // upcast
}
Questions:
1. Does pet lose all his Sss, Www, Ttt methods when he becomes a man? (even public Sss?)
2. What methods of the parent class does petya, who has become a man, have access to? Those. what is allowed: male.Aaa()? man.Bbb()? man.ccc()? (I'm especially interested in protected Bbb, because man.Bbb() gives me an error)
Thank you.

Answer 1

public methods can be called via cast:

if (мужчина is Y y)
{
    y.Sss();
}

or
or Access to protected methods is allowed only inside the class itself (if you add internal to the protected modifier, access extends to the assembly level), private methods are not virtual, they are not inherited. PS Well, you have identifiers ...

Answer 2

Absolutely nothing will happen to the pet - it remains an instance of class Y, which has access to both its own methods and the methods of the parent.
But you can't access them through the "male" variable without casting to Y.