Welcome @Mario_Diaz
This is a much older tool that has a bug in the wrapper. The tool is only hosted at the UseGalaxy.eu server (legacy reproducibility reasons) and not other others. Details are in this topic → troubles with footprinting tool - #4 by jennaj
But just in general, the input file contents are described here at the original author’s website.
And very simple examples of those files are in our Github repository for the Galaxy version of the tool wrapper. You can copy the “raw” version file link and paste those into the Upload tool to get any of them into a history for closer inspection.
For now, working with different tools would be recommended. The Galaxy Training Network (GTN) has example ATAC-seq workflows under the Epigenetics and Single Cell topic categories.
I wish we had a better answer but this is how it stands for right now! We hope it helps to explain what is going on. Unfortunately, even if you had the right input files, this tool cannot be executed in the current state. 