To insert a picture from the web in an email with Yahoo Mail:
1. Locate the image on a web site, or open it directly using its URL (address).
2. Highlight the image — just the image — with your mouse.
3. Press Ctrl-C (Windows, Linux).
4. Position the cursor where you want the image to show up in an email you are composing in Yahoo Mail. Make sure you have enabled the Yahoo Mail rich text editor.
5. Hit Ctrl-V (Windows and Linux) or Command-V (Mac) to paste the image.