how to fix javascript date function

I'm trying to make a web application that updates a list every day, but I'm trying to link the new day/date to a different PHP page that I have made.

function myFunction() {
    var d = new Date();
    var weekday = new Array(7);
    weekday[0] = <?php include'sunday.php';?>;
    weekday[1] = "Monday";
    weekday[2] = "Tuesday";
    weekday[3] = "Wednesday";
    weekday[4] = "Thursday";
    weekday[5] = "Friday";
    weekday[6] = "Saturday";

    var n = weekday[d.getday()] document.getElementById("subject").innerHTML = n;
}

My result that I'm trying to achieve is to have a new day link to a separate web page

I have come across another problem, I cannot or well don't know how to get the information from the other file and print it out onto the main file.

code from both files :

index -

<script>        
    function date() {
        var d = new Date();
        var weekday = new Array(7);
        weekday[0] = <?php include'sunday.php';?>;
        weekday[1] = "Monday";
        weekday[2] = "Tuesday";
        weekday[3] = "Wednesday";
        weekday[4] = "Thursday";
        weekday[5] = "Friday";
        weekday[6] = "Saturday";

        var n = weekday[d.getDay()];

        document.getElementById("subject").innerHTML = n;

    }

</script>

    <ul id="subject">
        <li id="room"></li>
    </ul>

sunday -

<ul>
    <li id="year">YR: 11</li>
    <li id="room">ROOM: DM8</li>
    <li id="teacher">TEACHER: K HA</li>
</ul>