Prismic contains all the content that you would like to feature in your website application, but this is all handled in the front-end code of a site when it comes to structuring and styling this content.
Creating well laid out Custom types gives content creators a general sense of the website's structure, but ultimately this is determined in the application.
It is possible to do some basic formatting for text using the Rich text editor can be overwritten and controlled by the developer in the front end.
If you are not a developer, then you will need some help implementing any styling changes in your website. If you are a developer, then you can style your application with any modern styling technology of your choice.