Is this statement true for all languages that support Object Oriented Programming?

Question

"An instance of the subclass is an instance of the superclass"

Answer 1

Subtyping and inheritance are fundamental concepts that describe the relationship between objects in OOP languages.
Here you can read about these concepts and how they appeared in the ancestor of all object-oriented languages: Simula and Smalltalk.
https://www.cl.cam.ac.uk/teaching/1011/ConceptsPL/SIMULA-Smalltalk.pdf

The implementation of these ideas can differ a little bit across languages, but the concept is more or less the same.

Answer 2

Not true only few like Java, C++, C#

Answer 3

Every programming languages has its own rules. Not all languages follow the same statement