Running emacs 25.2.2.

Here is something (apparently) simple I want to do, but am unable to:

• I am editing an html document. I want to see the same document in the internal browser in a vertically split window.
• Now, if I make any changes to my html document and hit a key (may be, save buffer could be the trigger), the browser buffer is updated to reflect the changes.
• The scrolling between the two buffers is synchronized

I can C-c C-v (browse-url-of-buffer) but that does not help because there is no way of updating the browser buffer. Moreover, the scrolling is not synchronized.

How do I get this done?