Good luck with your ambitions. I don't think you need any specialised software. If you are intending to write novels, or non-fiction, usually all that publishers require is the first chapter or couple of chapters, submitted on A4 size paper, in double-line spacing. It worked for me.
Suggest when you have decided what it is you want to write, that you obtain a copy of the Artists and Writer's Year Book to check which publishers are interested in what type of books or articles. When you have something prepared, it's as well to submit something to an agent to see if they are prepared to take you on as a client. In the meantime you could check out various types of magazines and periodicals, as they often pay quite well for shortish articles, or stories.
I imagine given your previous employment you should be good at proof-reading, which will cut down costs. Once again I wish you the very best of good fortune. Please let me know how you get on.