[R] how do I draw this surface -- hand drawn in the attachemtn

[gallon li]

Basially I have the observation for x, y, and z

for each fixed z, the value of y moves from 0 to y0 as x moves from 0 to x0.
I then move the curve for z from 0 to z0 and form a continuous surface. want
to know if there is a way that R can replace my handdrawing.
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