To open or "look into" a file with a extension, you need a file archiver that supports the 7z format. The most common and recommended tool for this is 7-Zip , which is free and open-source. How to Open a .7z File on Windows
: Right-click, select Show more options , then hover over 7-Zip . Extract or Open : To open or "look into" a file with
Select or Extract to "J1" to unpack the files into a folder. Alternatives for Other Platforms macOS : Use Unzip One or Keka to handle 7z files. select Show more options