To add text at the beginning/a-certain-place-from-start for all lines, just click there and do ALT+C and you will get the below box. Type in your text and click OK and it's done.



To add a certain text at end of all lines, do CTRL+F, and choose REPLACE. You will get the below box. Put in '$' in 'find what' and in 'replace with' type in your text.Make sure you choose 'regular expression' in the search mode (left down). Finally click 'replace all' and you are done.