A bit of an explanation?

Now for your first question, it looks like you have the correct idea, however this is not valid code:

public static class Woman {
    public Man husband = man;
}

the variable "man" here is not declared and can't be used in the block of code. A class is only a blueprint on how to create an object. A common analogy is like a house blueprint, it shows how to build a house, but it isn't a house. Think of a class as the same way: its a blueprint, not a house. In java an object is actually constructed using the 'new' keyword. While that code is not valid, I think you are just trying to assert your understanding of what the line woman.husband = man; is doing. In that sense you are correct in that it is setting the value of the "Man husband" of the woman object created. It is important to understand that it is setting the object's husband field and not the class field. Just like a house blue print can be used to build multiple houses, a class blue print can be used to build multiple object:

Man man = new Man(); // construct a Man
Woman woman1 = new Woman(); // construct a Woman
Woman woman2 = new Woman(); // construct a Woman
Woman woman3 = new Woman(); // construct a Woman
woman1.husband = man;

Here only the variable "woman1" has its husband field set to "man", "woman2" and "woman3" still have null values (non-existent) values for that field. That is like if you build 3 houses from the same blueprint, then paint one of the houses red. The other two houses will not be red too. Anyways, this is a complicated subject and Java books devote whole chapters to just this. You will get it in bits and pieces as you learn more, and solve more tasks. Watch the video I shared above.