Hello! What's the whole process in getting a new iPhone 5 charger?

Well, just so recently my iPhone 5 charger had stopped working , it doesn't recharge at all..

I thought it was dust in my phone, but it's not..

So I wanted to know the whole process to exchange my charger,

my warranty did not expire yet , but I'm pretty new when it comes to my phone..

Do I just go to any Apple store and ask for an exchange in my charger?

What do I need to bring (if anything)??

What do I ask for?

How does the process go?

( Sorry if this question seems stupid, I'm just looking for a very descriptive answer to specific questions)

Thank you!