You can do a File > Share > Email from the iMovie project screen to email your video. When the share (export) process is completed an email template will pop up that contains the movie. You then fill in the address and send. Your ability to send the movie would depend upon the file size limitations of your email provider. If the movie is too large to send, you could open an iCloud mail account that gives you the capability of sending a 5GB attachment.
Also, you should be able to import the video from your Sony digital camera to your Mac desktop by using the Image Capture app that already is on your Mac.
-- Rich