Well first off is you need to extract the file it came in, which is a .7z file. Windows 10 (if I recall correctly) is able to open such files, which are known as compressed files, but if not I recommend 7zip or WinRAR (preferably WinRAR) to extract the file inside. Place the file inside to a folder of your choosing, then go into Dolphin and select Options > Configuration and head to the "Paths" tab, then click on the "Add..." button and choose the folder with your GCN/Wii games and they should show up for quick playing.
"NintenDON'T sue me please haha"
I just downloaded the scrubbed Windwaker and am using dolphin 5.0 for my emulator. but I don't actually know how to start playing the game on it and couldn't find a video to explain it. does anyone have the link to a video or can just give me instructions on what to do? (I will love you forever)