Data does not belong to a controller.
The general rule is that database tables representing conceptual entities (Customer, Order, Cart, etc...) are fetched and modified via their namesake classes (the model). As long as you can construct a Customer
object in any given controller, you can access the corresponding data for that object from the database.
A controller only contains the logic that performs a certain action or group of actions. To achieve this, it usually interacts with one or more objects from the model because the controller itself stores no data of its own.
In this particular case, if you have access to the customer's id, you can pass that to the Customer
constructor and proceed to use its properties and methods.
Alternatively, the controller might have already set the $this->context->customer
property which contains an already-constructed Customer
object you can use.
Once you can access that data, you just have to assign the values to the smarty variables of your choice (via $this->context->smarty->assign()
) and you're all set to use them in your template.