How to modify HTML of specific node in Drupal 7?
Short answer: Place a customized template named node--[nid].tpl.php or page--node--[nid].tpl.php in your themes template folder. ([nid] = id of specific node).

Long answer: If you didn't done yet, you should first create a Bootstrap subtheme for your modifications. Then copy either node.tpl.php or page.tpl.php from the Bootstarp theme inside your subtheme folder. Rename the file to either node--[nid].tpl.php or page--node--[nid].tpl.php (Replace [nid] with the node id of the specific node) and customize the file to your liking. Lastly clear the cache at /admin/config/development/performance

For more/other template examples have a look at Drupal 7 Template (Theme Hook) Suggestions

EDIT: To control specific blocks for a specific page, I'd create a dedicated region inside your subtheme's .info-file and in your page.tpl.php / page--node--[nid].tpl.php. And place the blocks inside those regions.