stilt external staircase to duplex internal staircase

[manshiv]

Hello,

I have a south facing plot of 30ft width and 20ft depth. My plan is to have stilt floor & 2BHK duplex in next two floors.

In stilt floor I have external staircase. By extending the same staircase I wanted to use duplex stairs.

Can you please suggest how to do this.

Thanks
Manjunath