These fonts are downloadable as "F1.ttf". Instead, you must install the actual font families that your software expects.
Available via Ubuntu repositories or wadalab-fonts package. cid font f1 f2 f3 f4 f5 f6 f7 fonts free download work
When you see an error like "CIDFont+F1 missing," it means the PDF file was saved with "subsetted" or custom-encoded fonts, and the viewer cannot find the original font data it needs to render the text. Because these names are just labels (e.g., F1 might be Arial in one document and Times New Roman in another), there is no single file named "F1" to download. Common Identifiers and Their Likely Originals These fonts are downloadable as "F1