Both of your transcriptions are correct as far as getting the audio into text; the only difference between the two being the space. However, the first sentence doesn't make any sense. It doesn't have a verb. "Quién" means "who" (singular). "Quiénes" also means "who" (plural). If you know that the horse is owned by two partners you might ask "¿De quiénes es el caballo?" Unfortunately in Spanish, as in English, there may be more than one way to write what you hear. Sometimes you just have to know from experience. As for not being able to enter accents, check your keyboard settings. If you're using a Windows based computer, you can select the "United States-International" keyboard and use the apostrophe to make the accent marks. I can't help you with other operating systems, other than to say they usually have some method available.

Thanks, CalvoViejo. The error explanation noted that I forgot a space. Who, What, When, Where, Why, and How- and even How Many are the words I need to work on for now. I need to mull over these in print for a while. They are new to me and they look alike.