Help Me please, membuat textbox terisi otomatis

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#1

how to make a way to make, if textbox 1 is filled in then texboxt 2 will bring up a sentence that we have set, please help, I’m a beginner.

#2
  1. Please make your topic & post related to each other
  2. Show what you have tried…
    @Bayu_Agung_Setiawan
#3