Cost of learning

Hi all 🙂

I'm still getting my head around what's billed and what's not so need some help if it's going...

I'm studying for the Microsoft certs at the moment and want to know that if I create things like Azure Firewalls, Route Servers, Gateways ect... would I be billed for them just existing in the tenant or do they need to have data moving through them to generate a cost?

I'm wanting to get my hands on these resources but the pricing is a tad high on the calculator.

Any help is welcomed.

Kind regards

Tom