Install an archive tool that supports 7Z files
Windows: use 7-Zip, WinRAR, or PeaZip
Mac: use The Unarchiver, Keka, or BetterZip
Linux: use p7zip or your file manager’s archive support
Right-click the 7Z file
Select Extract Here, Extract to folder, or Open with the archive tool
Enter the password if the archive is protected
Open the extracted files from the destination folder
If needed, drag files out of the archive window to extract them