How to add HTML File into Doctype

I am beginner in Frappe. I don’t know about this. So Please help me.
I have created a “Demo” doctype. Through HTML, I want to create one table that contain one “add” button in last and “delete” button in each row. So whenever I’ll go to “Demo” list and click on create new “Demo” then I’ll only see table headers. Then I’ll click on add button then new row will be generated and i’ll edit that. Also I’ll show delete button in each row.

I want to create customise table.

If this is not possible then is it possible to add html file into Doctype whenever we create new document?

Please help me to solve this issue.
Thank You