Who executes first after fork() in Linux: parent or the child?

Question

I know that it can be either of these. But I always see that the parent executes first on my LINUX terminal.

• I used the same code on two different machine, one use kali Linux and the other Ubuntu , I got the same result.
• I searched for that and I got nothing.

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<sys/wait.h>

int main(){
    int id = fork();
    if(id == -1) {
        printf("error!");
        return 1;
        }

    if(id == 0){
        printf("I'm the child\n");
        printf("child\n");
        return 2;
    }else{
        printf("I'm the parent\n");
        wait(NULL);
        printf("child has terminated\n");
        return 3;
    }
   return 0;
}