InfoPath Data Validation

Hi! I am new to infopath and I'm trying to set up a couple of forms. Basicly what I'm doing is; the setup of a new starters checklist.

My question is: I want infopath to fill the date form automaticly when I thick the box in front of the field with todays date ( as seen in the picture attached ). I've tried with Rules and Data validation ( as seen in second picture ) but I'm not getting there since no value is added to the field. Anybody have a solution? Doesn't seem like a big query. Thanks in advance!!!
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