form input content on others input content forms

Question

Hi Sirs;

Someone can I help to transfert once from button an input content from the first page to three forms having on input each. Could you have a look on what I am trying to do. Its works but cannot transfert to the others pages. Thanks.

<!------page1---->

<center><form name="f1" action = "page2.php" onsubmit = "return validation()" method = "POST"> 
        <table>
            <tr>
                <td><label>User: </label>  </td>
                </tr>
                <tr>
                <td><input autocomplete="new-password" type = "text" id ="user" name  = "user"  value="" style="border:none; font-size:16px; background-color: white; color: black; width: 150px" pass="user"/></td>
                
                </tr>
                <tr><tr><tr><tr><tr><tr><tr>
                <td><label>Mot de passe: </label></td>
                </tr>
                <tr>
                <td><input autocomplete="new-password" type = "password" id ="pass" name  = "pass"  style="border:none; font-size:16px; background-color: white; color: black; width: 250px" class="pass"/></td>
                </tr>
                <td><input type =  "submit" name = "btn" id = "btn" value = "Login" /></td>
                </tr>
            </table>
        </form></center>

<script>  
            function validation()  
            {  
                var id=document.f1.user.value;  
                var ps=document.f1.pass.value;  
                if(id.length=="" && ps.length=="") {  
                    alert("blabla1");  
                    return false;  
                }  
                else  
                {  
                    if(id.length=="") {  
                        alert("Le champ Utilisateur est vide");  
                        return false;  
                    }   
                    if (ps.length=="") {  
                    alert("blabla2");  
                    return false;  
                    }  
                }                             
            }  
        </script>  

<!------page2---->

<?php 
$uname = $_POST['uname'];
?>

<form action="" method="post">
		<label style="font-size:50px">Hi customer...!</label>
		<input type="text" placeholder="" name="uname" id="uname" style="border:none; font-size:50px; color: #b22222; width:200px" value="<?php echo $uname ?>" disabled>
		<label for="nome"></label>
</form>