Instagram domain path as username algo

All of us knows Instagram domain of any individual's account looks somthing like: Instagram . com /username

How to make such kind of algo which makes a new path in website, uses username of person as path name.

Will this much (in php ) will work:

$username = 'users-input'; header('location:Instagram . Com / $username');

Or do I have to automate the entire process using selenium (python). Or something else

Please drop the answers,it will be really helpful. Thanks in advance.