If you've not yet done so, you could try a Spotlight search on ".pages"
It will have a large number of hits, as it should find all the Pages files on your Mac.
Looking further:
If your accidental deletion was recent, and not much has been saved (by you, other users of the computer, or by the computer itself), it may be possible to recover the file.
In past times, 'deleting' a file removed its entry from the directory of the device holding the file, and marked the space holding the file as 'available', but did not actually remove the file. But having its space marked 'available' made it vulnerable to being overwritten by any data being saved after that deletion, and once overwritten, it was no longer accessible.
There were applications available then that could find the bits and reconstruct some or all of the file, and there were (and probably still are) data restoration companies with more powerful applications that could do a more intensive search for parts of the file, spend more time at it, and could, in some cases, restore even partially or completely overwritten files. Those talents came with a large price tag, though, and probably still do.
A net search for 'data recovery software' may bring up some affordable candidates, or may serve as an object lesson on the importance of backing up as least the important files.
Good luck!
Regards,
Barry