[javascript] HTML button onclick event

Try this:-

<!DOCTYPE html> 
<html> 
<head> 
    <meta charset="ISO-8859-1"> 
    <title>Online Student Portal</title> 
</head> 
<body> 
    <form action="">
         <input type="button" value="Add Students" onclick="window.location.href='Students.html';"/>
         <input type="button" value="Add Courses" onclick="window.location.href='Courses.html';"/>
         <input type="button" value="Student Payments" onclick="window.location.href='Payment.html';"/>
    </form> 
</body> 
</html>