Is it possible to have different pages for different categories in ghost?
Yes you can. Categories in Ghost are called tags, and the details of how to create a template for a particular tag are covered in the documentation for the tag pages and for templates.
To explain, each tag gets a 'slug' which forms the url. E.g. the default tag already included when you install Ghost is 'Getting Started' which has the slug 'getting-started'. The tag page can be accessed at yourblog.com/tag/getting-started/ and you can create a template for it by using the filename tag-getting-started.hbs.
Note: you will need to restart Ghost for it to detect new templates after adding the file.