is it possible to save a pdf as an image for the inability to edit? and is it possible to recognize the font in the picture?

1. simply export to PNG for example

2. after rasterisation? There are online service like "Font-matcherator" which will help to identify Font names. Or in the PDF? When text isn´t converted to paths it should be readable by the Text and Font tool under "Collections" or mentioned in the XML

Another way:

1. Create a new layer on top
2. Select all in all layers
3. Alt + B to make a bitmap copy of all selected
4. Shift + PgUp to put the new image on the top layer
5. Right mouse button on the top layer to get menu: Hide all other layers
6. Save a copy as PDF.

To make revisions: undo hide all layers and delete the top layer. Start at step one when ready to save a revised copy as pdf.