Questions about Apple Certified Technician

Hi!

So I want to get Apple Certified Technician and I have some questions!

I want to begin with iPhones and display/battery replacements.

1. Does it cost anything? If so, how much?
2. I have logged in to GCX, and i've read that I need access to ATLAS. How do I get that?
3. Does the certification expire?
4. Where do I start?

I have a techician-ID.

Sorry for my terrible english and thanks for reading this/helping me!

Best Regards

Edi aka "Sadeem"