Customize backend create view of Dynamic content items in si

Hi All, I am new to sitefinity and have created a dynamic module called press release with 10 fields. So now i have following requirement:
 
1) I want to change mark up of create/edit backend view.
 
2)Add preview button in create/edit backend view.
 
3)Add status logic to show approved or not based on approval status.
 
Also please let me know how I can open "create backend view" in visual studio and change the markup ?
 
Currently I am working on licenced sandbox and i have access to sanbox project files. Please help me in above requirements. Thanks in advance.