If I write my code primarily in a way that is simply supposed to achieve functionality then it's by definition functional programming.

Regardless of the language used!

Sure, I agree that you can write C in a functional style, but you wrote that C was a functional language.

> C in indeed a functional language […]

… which it isn’t, it’s imperative ¯\_(ツ)_/¯

Is this possible that you could give me some example project, for instance, that makes of C imperatively?

Probably depends on at what level you see things. If you visit and probably live in Japan, then you develop the concept of 'cryptocurrency'. You then subsequently develop intellectual property around the 'concept' of 'cryptocurrency'.

Is this really 'imperative' programming? I'd say not but depending on at what level you see things, then it could be.

At project level, then it's purely functional.