Since you cannot download a font called "F1," you must use alternative methods to make the text readable or editable. 1. Embed Missing Fonts (Adobe Acrobat Pro)
Since you can't download these placeholders, the solution is to replace them with the standard fonts they were meant to be: CID+ Fonts - Adobe Community cid font f1 f2 f3 f4 f5 f6 f7 fonts better free download