Here comes a step-by-step guide:
1. Edit the file from which you want to copy text
2. Put the cursor onto the upper line to be copied
3. Mark this line (press ma
4. Go to the lower line to be copied
5. Pull the text from the current location to the line marked with a (press y'a
6. Open the file to paste the text into in the same terminal using the vi command :split filename
7. Go to the line where the insertion is needed
8. Paste the text after the cursor (press p
9. Save and quit.
Hope this helps!