If the font says "Not Embedded," look up the legitimate name of that specific font and download it from an official foundry or trusted repository (like Google Fonts). Method 2: Download the Official Adobe Acrobat CJK Font Pack
Searching for "Cid Font F1 F2 F3" typically leads to results related to rather than a specific typeface you can "download" in the traditional sense. What is CIDFont F1, F2, F3? Cid Font F1 F2 F3 Free Download
The PDF file may have sustained data corruption during a download, email transfer, or file recovery process, breaking the font maps. If the font says "Not Embedded," look up
If you are seeing these names because a PDF isn't displaying correctly, use these methods to restore the text: CID+ Fonts - Adobe Community The PDF file may have sustained data corruption
The creator embedded only a "subset" (only the exact characters used in the document). If the PDF gets corrupted or edited later, the system loses track of the character map, resulting in unreadable text. How to Fix CID Font Errors Without Downloading Files