Example:

#include <stio.h>

int main(void){
	printf("Hello world");
	return 0;
}

Output

prog.c:1:18: fatal error: stio.h: No such file or directory
 #include <stio.h>
                  ^
compilation terminated.

How to fix?

See the header fie inclusion section, I wrote #include <stio.h> instead of #include <stdio.h>, to fix this or such errors, we should use correct header file names.

Correct code:

#include <stdio.h>

int main(void){
	printf("Hello world");
	return 0;
}

Output

Hello world