How to get a selected text (in label or textbox) by clicking first to find the start position and clicking a second to find the end of selection

Hello Members,
I would like to find a way to have a part of any text in label text or text box just in one click to indicate the start and a second click to find the word for last selection. There is the same function with the keyboard by clicking a longtime but the inconvenient is its not so fast and usefule for me and there is the option copy etc… What I want is to do faster and easier a copy a selected text by clicking the first word and a second click to indicate the last word to copy. Thanks a lote for your help Guys