Not quite sure why Mr. Parker asked you your router's SSID; he must have still been half asleep when he asked this. Not his typical good advice. So, moving on . . .
I have set up over a half dozen Alexa devices of all three models. Some went smoothly; some did not, but eventually all are working fine.
First thing is, the Echo sounds like it has its brains scrambled with bad cached data. The best idea I got from Amazon's online instruction for trouble with setup is to unplug the device for at least five minutes so the circuits of the device get totally cleared.
Are you using the Alexa app to do the setup, and on what device: phone or tablet?
After five minutes are up, plug the Echo back in, let it get setup and tell you to proceed. Follow the verbal instruction and those on the app. First you need to be connected to the Amazon-XXX internal wi-fi of the device, and when that happens it will tell you to select your home wi-fi signal, and if you see one for both the 2.4G and the 5G signals, select the one for 2.4G (you will have better range on this one). Enter your password for the SSID. Device will tell you it can take a minute or two to connect, and when it does, your Echo should be connected to your home network and internet.
If you experience problems, unplug again for five minutes and follow steps for setup again. Let us know if you get it setup; you likely will!