The process of registering a customer is mainly done in the POS or through a loyalty solution.
You can also create customer profiles via Portal.
Navigate to the Customers menu to create new customers or manage existing ones.
If some of the customers are your employees, then you might want to set a standard discount for them when purchasing products from your company. To do so, toggle ON the setting Is employee and choose a value for the standard discount.
Watch this video below to know more on how to register a customer as an employee.