Hi,
First of all you need to create your page template. If you are using ASPX templates, please follow this documentation:
http://devnet.kentico.com/docs/devguide/creating_a_new_aspx_page_template.htmIn the example from the documentation, you can find a way how to add editable region control to your page template.
If you are using portal engine approach please follow the documentation on how to create page template in portal engine:
http://devnet.kentico.com/docs/devguide/creating_a_new_page_template.htmYou can then edit content of the editable regions on Page tab. If you are on the newly created page and in design tab in cms desk you are not able to see any zones or web parts, please check if your master page template contains “page placeholder” web part. I have already mentioned this in this thread. This web part is responsible for loading the content on your sub-pages. So, if you miss such web part on your master page (root) you will not see anything on your sub-page if you are inhering content from master page.
Then you just need to navigate to CMS desk and create new page using the page template you have created. Once you save the page, you will be able to add content to editable regions on the page.
Best regards,
Miroslav Remias.