Do you want to select lines in program code?
Do you mean lines on screen or paragraphs? Lines depend on word wrapping, text may be wrapped differently if user resizes window. Paragraphs are added when user presses Enter key, they do not depend on window width and word wrapping.
Do you need to copy all content of TRichView between '*' characters?
I.e. the code should search for the first '*', remember it location, search for the next '*', and copy fragment between them.