If you want to insert text inside your EditText view that stays there after the field is selected (unlike how hint behaves), do this:
In Java:
// Cast Your EditText as a TextView
((TextView) findViewById(R.id.email)).setText("your Text")
In Kotlin:
// Cast your EditText into a TextView
// Like this
(findViewById(R.id.email) as TextView).text = "Your Text"
// Or simply like this
findViewById<TextView>(R.id.email).text = "Your Text"