Question: Can i use a login in master page & how can the label in master page eX: welcome Tony appear to all other pages 

Answer: Your log-in must be attached to some sort of database (e.g. MySQL). When logging in, your script should test username and password entered against records in DB. Each subsequent page then can 1. check to see if a user is logged in, and 2. if they are, pull that name out of the DB and display it. Your actual script would say something like "Welcome <?php echo $username;?> (using PHP as an example)
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