Send HTTP 200 response from socket server

Question

I am trying to send response to client, whenever I add HTTP/1.1 200 to my buffer, the server wont start,whenever I go on localhost:18000 it loads forever. Without the http/1.1 200 it starts but I want to send a http response. Am I doing something wrong?

#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <string.h>
int main()
{
    int socket_server = socket(AF_INET, SOCK_STREAM, 0);
    int port = 18000;
    char buffer[2000] = "HTTP/1.1 200 OK\nHello";
    if (socket_server == -1)
    {
        return printf("Error in socket function");
    }

    struct sockaddr_in addres;
    addres.sin_family = AF_INET;
    addres.sin_port = htons(port);
    addres.sin_addr.s_addr = INADDR_ANY;

    int bind_server = bind(socket_server, (struct sockaddr*) &addres, sizeof(addres)); 
    if(bind_server == -1) {
        return printf("Error in bind function");
    }

    int listens = listen(socket_server, 0);
    if(listens == -1) {
        return printf("Error in listen function");
    }

    for(;;) {
        int accepts = accept(socket_server, NULL, NULL);
        send(accepts, &buffer, sizeof(buffer), 0);
    }

    return 0;
}