Dc adjustment0-5volt

Hi i want adjustment dc step up 0-5v adjustment by arduino uno r3 adjustment Zener diode KIA431A help me please i want adjustment by arduino Electronic circuits adjustment in put 0-5v settings volt out put step1 0-5v 30% step2 0-5v 50% step3 0-5v 70% step4 0-5v 100%

In put 0-5v from drive by wire

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