This specific filename suggests it is the 10th version (indicated by the (9) ) of a generic file named "j" that was downloaded to your device. Without more context, I can't see the contents, but here is what that usually means and how you can access the text inside: What is this file?
: This is a compressed folder. It acts like a digital suitcase that holds one or more files to make them smaller and easier to transfer. Download File j (9).zip
: Tap the file; most modern phones will show a "Preview" or "Extract" option. This specific filename suggests it is the 10th