If i bought pages for my phone and ipad do I get it on my computer too?

Welcome to the Apple Support Communities

When you purchase Pages for your iPhone, you can install it on all your iPhones, iPads and iPods touch for free, but not on your Mac because it uses a different Pages version. You have to purchase Pages for Mac to use it on the computer

You will need to purchase the computer version separately.

And ... on the OS X Pages version, the PDF user guide can be accessed via the Help menu.