Help with using text to speech?

Hello,

my computer doesn't have a microphone. i think there is a thing where i can type and then the computer will read what i type.

if it does, how do i get to it, and will it read as i type (or does it have to typed before hand,

because i can use google voice to make calls and when i call my husband on it i can here him but i need a way to talk to him as well.

i'm really really sorry if this is a dumb question but i'm not not that good with computers.

thank you so much!