To remove a hyperlink, select the item in your file, click Insert > Hyperlink > Remove Link.
If you want to remove multiple hyperlinks, press +A to select all text and then press +6.
Note: You can use the keyboard shortcut to remove all hyperlinks only from Word for Mac.
However, this command doesn't remove hyperlinks from pictures. To remove hyperlinks from a picture using a keyboard shortcut, you'll need to use VBA macros. Here's more information on what macro to use.