there's a tutorial for how to download tts lines on youtube. something about how to make a voice like glados from Portal.
There's also AI voices but even that costs money.
If your just looking for easy ways to do voices, I would recommend something more like Banjo Kazooie(I think this method is called Babbles), sounds that tell you this is the character talking, and can change depending on tone, but are not directly saying each word.