Question

difference between landfill and empoldering in very easy way.

Answer 1

Landfill involves dumping enough soil, garbage, rock, etc. to raise the surface above the water level (sea level, lake level, etc.). Empoldering is the walling of an area and removing the water. 

Availability of fill material favors landfill. Empoldering requires years of maintenance to pump out water, desalinate the soil and otherwise improve it. In the end, the land is still below water level and inherently vulnerable to flooding. (Parts of New Orleans are below water level because the river deposits were constrained, raising the riverbed - but they offer a good illustration of the risk.)