Hi Fahad,
If I may ask, what exactly is the use case for wanting to create many pages at a time dynamically?
We launched a Migration API in closed Beta, which is designed to migrate large amounts of content into Prismic. It's currently available for testing via a waitlist.
It's not designed specifically for what you mentioned, and you need to make one request per document, but it may perform some aspects of what you are trying to achieve.
You can read more about it here and sign up for the waitlist: Document Write API - #13 by alaina.koerber
Or look at the technical documentation: Migration API Technical Reference - Documentation - Prismic