If you have Office 365 you get Dictate added to Outlook and Word
It is on the home ribbon. To end sentences you say stop and for commas you say comma. Have't experimented with all the other punctuation yet.
Otherwise, use the GBoard (Google Board) on an Android device. It has a text to speech option too/ Dictate. You can then just put it in your One Drive or Google Drive.
I use those so don't know of any free ones. Dragon software is what I have used at clients before
When I bought it I was surprised to find an older home version (ver 13) for R800, with a mic, on importitall . the price included shipping from UK and tax/duty. I think I found it doing a Google search and was taken aback by the price as importitall is usually very expensive.