Add Customer Store Number Information from MySQL database to Wordpress Welcome Email by remymedranda

I have a mysql database where we have uploaded all customer emails and store ID's. This was uploaded outside of Wordpress. I need to Upload these emails into the WORDPRESS database so not only it creates users for these emails, but also adds a field of data called Store Number... (Budget: $2 - $8 USD, Jobs: HTML, MySQL, PHP, Wordpress)