https://speechnotes.co/
This FREE
You basically just go to the Speechnotes website and start talking. What you say is transformed, as you talk, into text that you paste to whatever website or document you wish.
It has made writing messages for the thisisms.com website far easier for me.
Also, Do proof read what you wrote !Works entirely online in your Chrome browser. No download, no install and even no registration needed, so you can start working right away.