If you want to quickly try out human like automated text-to-speech, this is what you can do:
Download Audacity -- a free open source Audio editor
Then go here: cloud.google.com/text-to-speech#section-2
First time you use that form, you would need to solve a captcha.
Then type your text there, choose the voice you want Google to use to generate and be ready. Return back to Audacity; and choose the option of picking up the input from your computer itself; instead of the microphone.
On windows, Audacity has this capability built right in.
On a Mac, you would first need to install a software called "blackhole" existential.audio/blackhole/?pk_campaign=gi.. and go to the System Preferences, Audio -- and make sure both the output and input are pointing to "Blackhole" -- the virtual mic/speaker. Effectively, it is like taking an audio cable to take the output from the mac and feed it back into the input (Which is also an option, if you want. That's called a loopback cable)
Once Audacity is all configured; press the Record button there. Then just simply go to the speak button on that Google page; and click that! The audio generated by Google would be captured by Audacity.
Rest, I am sure, you can do by yourself. Enjoy. But please do not misuse this loophole else they may discontinue that page.