Include HTML into ASPX and buttons

Hi everyone

I'm an situation that I don't know how to solve. First, I have several files
which will be generated from database and saved under html format and store
in a different folder (this was created by so else which does not include
buttons for me).

Because I need to include those files into my application. I have used this:
Response.Redirect("filename.html") to output the entire html file into my
aspx page. Unfortunately, I still want to maintain my page to keep
going further to next instructions. I want to have 2 buttons below those
files. I don't know how to do that. I thought if using placeholder can solve
the problem and how?

Thanks.