"CIDFontF6" isn't typically a commercial font name like Helvetica or Times New Roman. Instead, it is a or a subset name created by PDF generation software (like Adobe Acrobat or CAD programs).
– A free software project providing CID fonts for CJK users including glyph variants for different regions cidfontf6 font free download link
If you are the creator of the PDF, the problem is your exporting software. "CIDFontF6" isn't typically a commercial font name like
If a PDF creator utilizes CIDFontF6 but fails to embed the font directly into the PDF file, any subsequent reader or viewer will throw an error or display unreadable "gibberish" characters. Why Am I Seeing a CIDFontF6 Missing Error? If a PDF creator utilizes CIDFontF6 but fails
If you are looking for free, high-quality fonts for your own projects, use these reputable libraries instead of searching for "CID" tags: