It sounds like you're working with a .7z file (PineFalls2-Final-pc.7z), which is a common format used to compress large files, often games or software projects. Using 7-Zip or PeaZip to open this will allow you to see the contents, likely using the efficient LZMA2 algorithm, which is great for shrinking file sizes for easier sharing or storage.
Based on your comment, here’s a quick overview of what that file type means:
You'll need software like 7-Zip (Windows) or Keka (Mac) to open it. What are you trying to do with this file?