Top bar for Login

Question

I have a top bar on my site, for login client. Such bar is integrated with WHMCS, but I want that when the client is logged in, the bar changes from (LOGIN) for (Olá! Fulano), with some WHMCS panel options.

But I don’t know how to do it, someone can help me?

Code used:

<div class="top1">
    <div class="row">
        <div class="col-sm-3 text-top">
            <h7><i class="fa fa-sign-in"></i>  LOGIN</h7>
        </div>
        <div class="col-sm-9">
            <nav id="desktop-menu1">
                <ul class="sf-menu" id="navigation1">
                    <div class="row">
                        <div class="top-login">    
                            <form method="post" action="http://cliente.core-webhosting.com.br/dologin.php">
                                <input type="text" name="username" size="35" placeholder="  E-mail" />
                                <input type="password" name="password" size="15" placeholder="  Senha" />
                                <input type="submit" value="  Login  " />
                                <input type="button" onClick="javascript: location.href='http://cliente.core-webhosting.com.br/register.php';" value="  Registrar  " />
                            </form>
                        </div>
                    </div>
                </ul>
            </nav>
        </div>
    </div>
</div>

Codes I found:

    <? php
require ("dbconnect.php");
if ($ _ SESSION ['uid']) {
$ result = mysql_query ("SELECT Nome FROM tblclients WHERE id = '" [uid'] "LIMIT 1;" $ _ SESSION. '.');
    while ($ linha = mysql_fetch_array ($ resultado))
       echo "<p id = 'login'>". $ _ LANG ['welcomeback']. ','. $ row ['firstname']. ' | '. $ _ LANG <a href="/whmcs/clientarea.php"> <strong> [' clientareanavdetails ']. "</ strong> </a> | <a href="/whmcs/logout.php"> <strong> '[logouttitle']. "</ strong> </a> </ p> '_ $ LANG.';
}

another

{
    echo "<p id = 'login'>". $ _ LANG ['por favor']. ' <a href="/whmcs/clientarea.php" title="Login"> <bold> '. $ _ LANG [' loginButton '].' </ bold> </a> '. $ _ LANG [' ou ']. ' <a href="/whmcs/register.php" title="Register"> <bold> '[clientregistertitle']. '</ bold> </a> </ p>' _ $ LANG. ';
}
?>

To put in the index.html:

 <? php
include ('pathto / whmcs / login_status.php');
?>