Unfortunately, it's unlikely that you will be able to retrieve your changes and formatting from a .txt file that you have edited and saved in Word. .txt files are plain text files that do not support formatting or the addition of comments. When you open a .txt file in Word, it will prompt you to convert the file to a Word document format, which will allow you to make changes and add formatting. However, if you saved the changes back to the .txt format, it would have overwritten the original file with the unformatted text.
If you haven't closed the file yet, you could try using the "Undo" function in Word to see if you can undo the changes you made. If that doesn't work, you could also try using a file recovery tool to see if you can recover an earlier version of the file before you made the changes. Some examples of file recovery tools include Recuva, Disk Drill, and EaseUS Data Recovery Wizard. However, please note that the success of file recovery depends on many factors, and there is no guarantee that you will be able to recover your changes.