i am not able to understand the law of multiple proportions well so please define it with some common examples and a simler definition

Dear Shubham

This law states that “When two elements combine to form two or more than two different compounds then the different masses of one element B which combine with fixed mass of the other element bear a simple ratio to one another.”
For example: Carbon forms two oxides in oxygen
Carbon monoxide
Carbon oxide
The ratio of masses of oxygen in CO and CO2 for fixed mass of carbon (12) is 16 : 32 = 1: 2.