I went through my bank website, not the banking app, just because I was already on my laptop.

Login, go to the account.
Send money with Zelle
Email or phone number of the recipient
Enter amount
Confirm correct email or phone number
Send money button
Confirmation page with confirmation code

The first time I used Zelle it did ask for a confirmation code that was texted to my phone.

I think @cwilli26 is right, it varies a little bit. I was never asked to check business or individual.