I am using a very primitive veersion of C++ which is Borland Turbo C++ 3.0

I want to ask who makes the .exe and the .obj files after the compilation.

Is it the compiler itself or something else.

I know that the compiler of this version of C++ is written in C (the code shows that of the .h header files). How is it possible to create a language in itself.
How can the compiler be tested if the compiler is not complete as its code cannot be written in a few days.

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