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When changing the value of a variable in C, is the new primitive created or the current primitive mutated?

I know that “mutable” and “immutable” are terms that should be used to describe the ability of objects to change meaning in object-oriented languages ​​such as Java and Objective C. However, I would like to raise it because it refers to mine a question about these primitives. I know that when I change the value of a variable containing an immutable object, I actually create a new object. It is interesting, however, if primitive data in C behaves similarly to immutable objects. By this I mean that when I change the value of a variable containing primitive data, new data is created and refers to the variable. Or did existing existing primitives actually mutate / modify stored data values?

Edit # 1:

Problem # 1: I would like to clarify some misunderstandings (for my part or with others), because I did not make it clear when I said: "When I change the value of a variable while holding an immutable object, I actually create a new object." When I said this, I did not want to assign a variable to an existing object. For instance:

// Example 1: I did not mean this
-------------------------
String x = "Hello World";
String y = x;
-------------------------

// Example 2: What I meant is this
-------------------------
String x = "Hello World";
//This will print out "Hello World"
System.out.println(x);

x = "Goodbye World";
//This will print out "Goodbye World"
System.out.println(x);
-------------------------

Of course, by assigning the variable y to the variable x, as in Example 1, which was the case when you guys brought up, only the reference variable y refers to the object referenced by x. Of course, in this case there is no new object; only the same "Hello World" object referenced by 2 variables.

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-------------------------
int x = 10;
x = 2;
-------------------------

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-------------------------

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    return 0;
}
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