Design question

What is the best practice for automating the creation of a presentation? I
have a presentation that retrieves data (via web service calls) and then
displays it on 1 or more new slides. However, much of the look and feel of
the presentation is static. Should I make a slide master or template? I know
practically nothing about these things. I am a coder by trade. The VBA has
been easy, but the PowerPoint stuff has been exhausting.

If I could somehow reuse a template and then add the dynamic data to
pre-defined fields on the presentation that would be perfect.

Thank you all in advance for your help.

What is the best (or most common) practice for doing something like this?