See the pad API docs and
https://github.com/johnyma22/etherpad-lite-pad-manager
Etherpad is open source, if you need a feature you have some options....
a) Read the docs and make sure the feature doesn't already exist
b) Write the feature yourself
c) Put in a feature request on github and someone else might make it for you (FTFY)
d) Contract in some of the foundations developers, funding allows us to prioritise feature requests.
If you require a quotation for a specific feature please feel free to get in touch.
Thanks
John