Generally, most right-handers use the inside of their left foot, as this is the foot the usually ends up next to the ball.
In any event, I think an overwhelming majority of bowlers use their slide-foot whichever that is.
That said, there is no right or wrong, as stated previously, it's whatever you like. Although I'd be interested to hear the rationale behind targeting using the non-sliding foot, I'm unclear on what you mean by "so i can target my area"
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Reporting from England