PeterH:
caneryikar:
I am the one who will simulate the battery consumption. let's say like if 3 person is onboard battery will be discharged 100mA/min or no person on board 65mA/min, or the road conditions (uphill-downhill) and so on.Given that you're a third year student and taking responsibility for managing battery discharge rates, it's rather alarming that you don't seem to know the units for current.
It's feasible to simulate a battery discharge as you describe, but I don't see the point. If that's all you want, you might as well write a PC application that prints down a sequence of numbers from 100% to 0%. Wouldn't it be more meaningful to demonstrate that you can measure the actual discharge of a real battery and track the battery charge level accurately?
Well, yes it would be better if i could measure the actual discharge of a battery and charge level but i don't know how to start it with arduino.
and also i might not be knowing units properly, i am here to learn, so teach me master PeterH, seriously 
measuring the actual level is perfect, but i also got to have a simulation model.