voice to text

I have considerable hearing loss, I would like to have a small computer that will convert voices to text on the screen so I can read what people are saying to me. I would also like to convert voices recorded from the internet to text. I would like a computer small enough to carry but not so t small that the text is tiny and hard to read. What Dell computer would be best for this use? What software would I need to convert voice to text? Does Dell have that too? Thank you, Bill Vanderkooi