2D map generation with rules

Hello, i want to procedurally generat a map with certain rules: The player looks at a randomly generated map consisting of 4 or 5 pathways connected from left to right Pathways undulate (May have up and down ramps in them). Pathways must not have steps in them (Use appropriate east/west ramps). Pathways may be partially concealed by other pathways in front of them. Every Pathway has at least three consecutive visible, unconcealed blocks.

i have no clue how to do it any tips how I could go about programming this would be much appreciated