Let me break this down for you, because you are likely wasting your time. An .epub (Electronic Publication) file is not a game patch. It is not a .exe , .zip , .upk , or .u file. It is an e-book format designed for reading on tablets, phones, or e-readers (like Kindle, Apple Books, Calibre, etc.).
If the file is only 50KB or 100KB and claims to be a "working patch," delete it immediately. Run a virus scan. Malicious actors often disguise malware as .epub files (though rare, it happens) or simply rename junk files to trick you. Red Orchestra 2 Heroes Of Stalingrad English Patch.epub
If you found this .epub file on The Pirate Bay or some random forum from 2014, it’s not going to make your German soldiers shout in English. It’s just a poorly labeled strategy guide someone uploaded. Let me break this down for you, because