How can I implement Google Plus in the toolbox section in si

Hi,
How can I implement Google Plus in the toolbox section in sitefinity 5

Not quite sure what is your exact need but I supposed you can create a simple widget (ascx control) that only has the Google+ javascript?
Then you will need to register that widget in the Sitefinity Administration so it appear in the toolbox.
After this you are free to paste it to any page or template you wish (some more tweaks may be needed).
This video may be helpful:
http://www.sitefinity.com/devnet/video-tutorials/pages-management/how-to-create-a-sitefinity-widget.aspx