You don’t have to buy anything. Go to this page and subscribe for $9.99 a month. If you just have one document to create, you can cancel the subscription when you’re finished, or you could even create as many as you can in a month, then cancel. There’s no limit to the number of documents, and my novel is a 150,000 word document that I was able to make several times (correcting some errors). The instruction are fairly simple. The document you create can be read by the free version.