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You can check this guide to learn more about conditional logic: https://www.jotform.com/help/57-Smart-Forms-Using-Conditional-Logic
For the specific functionality to make fields require or not based on user's input, you can refer to this guide specifically: https://www.jotform.com/help/367-How-to-Make-a-Field-Required-Based-on-User-s-Answer. That guide is also mentioned in the first link I shared.
I hope that helps.