Is it possible to slice an image in Photoshop, add hyperlinks to
certain image areas and embed it into a Drupal CMS page?
Yes, after you have made your slices using the Slice Tool (C), use the Slice Selection Tool (C) and double-click on the slice. A dialogue box of options will open. You can add the Hyperlink to the URL spot.
I am new to this, but looks like it's possible to add a source of HTML
code in the CMS.
You can use File -> Export -> Save for Web (Legacy). Then save. Under format, choose HTML and images. This will create a HTML file with your images. I would NOT recommend using this process to create a website or web pages.
Is it sufficient to export images in html from Photoshop, or should
the DreamWeaver be involved for this?
I would use Photoshop to create images and a text editor (or Dreamweaver) to write the code for the website.
Also, the sliced image should be stored on the server?