On its current state, Marketo does not generate that type of report. This is a critical type of report that is currently missing.
I manually created a report like that a few months ago, by going to each template "used by" list and grabbing the list of pages, doing the same for all the forms, and then combining the data using vlookups in excel. Needless to say, it was a painful excercise that I will most likely never do again as I manage over 3,000 pages with hundreds of template/form combinations.
I was however able to work with my Marketo Premier support team a one-off report generated by their engineering team. This is not a common practice but now I have a clear idea of the inventory I have live. The report included page name, template, form, and status.
There is an idea running for this, so the more votes we get on it, the better chances we'll have to see it available in the future.
Thank you,
Rafael