If you are trying to open a file that says these fonts are missing, downloading a "CIDFont" file will rarely work because the label is unique to that specific document. Instead, try these solutions:
When a document is created, the software assigns generic names to the fonts used to save space or manage resources: Cid Font F1 F2 F3 Download -
Because CIDFont+F1 isn't a single commercial font you can purchase, you cannot simply "download" it. Instead, you must fix the way the PDF handles the missing information. If you are trying to open a file