How do you set a requirement in the text field? I am trying to program the user to have a certain email address in order to submit the form.
You should check the text string when they submit the email address, not when the text input changes.
There is a block you can use to check if a string contains some piece of text. Using a conditional you could set up blocks that would do the function
if the string “X” contains text “bla bla bla” then do something else