Like the Post options, there are also two ways to add media files into your page, they include:
Upload media files directly into page by selecting the file from the computer
Choose the media files from the existing files in the media library
If the first option is to be used, FileBird gives you the chance to select an already created folder category and then upload the file from your computer that automatically goes into that selected category and clicking on "Select" button will insert the media file into your page.
If the second option is to be used, FileBird also gives you the chance to select files to upload from the list of dropdown folder categories which are already created in your library area, thus clicking on "Select" button will insert the media file into your page.
See image reference for the insert image functions for pages and post below: