Gravity-fed irrigation can be practical where water is stored above the field, but the usable pressure depends on the vertical difference between the water level and the irrigation zone as well as losses through pipes, filters and fittings.
A village system should prioritize simple operation, accessible filters and valves, clear flushing points and components that can be maintained without specialized equipment.
Sloping land may need separate zones so that one part of the field does not operate under very different pressure from another. Water-storage capacity and refill time also need to match the irrigation schedule.
Before purchasing a kit, map the source, tank location, field elevation and crop rows. That information is more useful than choosing emitters based only on farm area.