tar xvfz go-ipfs.tar.gz
This is what pops up.
tar: Error opening archive: Failed to open 'go-ipfs.tar.gz'
I checked the downloads folder and the gx folder is there and so is the tar file.

The instruction are misleading a bit the file is named go-ipfs_v0.4.13_darwin-amd64.tar.gz assuming you are using the 64 bit version of OS X.
Thanks! What do I do next?
Downloads elaineyu$ tar go-ipfs_v0.4.13_darwin-amid64.tar.gz
Usage:
List: tar -tf
Extract: tar -xf
Create: tar -cf
Help: tar --help
I'm not a computer programmer so I'm not sure.
tar xfvz go-ipfs_v0.4.13_darwin-amid64.tar.gz
This is not really the place to get support, https://discuss.ipfs.io would be better.
I believe osx can also extract it for you if you use finder.
Most helpful comment
This is not really the place to get support, https://discuss.ipfs.io would be better.