Ok so I’ve never owned an Apple “laptop” before until today. I bought an older (2008 model) Macbook Pro.
Its not bad but the OS was 10.5!!! So basically you can’t get the lastest version (10.8) because you need 10.6 to even download 10.8 even though 10.8 will install on 10.5.
Here is a great article for installing from a USB drive/stick.