With a few pdf's I used I was able to edit them in Adobe Acrobat, but when I open them in illustrator I can't edit them at all. I try to release the clipping mask but noting happens. It seems like one big picture.
Here a clipping of the way I can edit in Acrobat
Sorry to hear about this issue. Could you please confirm in which application PDF was actually created? Illustrator can only edit vector PDFs which were created in Illustrator itself and saved with Illustrator Editing Capabilities.
Refer to this help article for more details: Adobe PDF options | Illustrator
Go to the "Edit PDF" window in Acrobat, select what you want to edit.
Then in the format bar, open the dropdown menu "Edit Using". Pick Illustrator. Illustrator will then just open what you've highlighted as an editable graphic.
Illustrator is NOT a general PDF editor, no matter how much it appears to be, no matter how much people want it to be, and no matter how much Adobe marketing may try to present it as one.