By the way how much is the potential earning in that kind of business, never have any idea as i was not interested with faucet related thing before
That's dust, just dust
The earnings from faucets are really minuscule and worth neither time nor effort. They in fact might have made some sense for, say, unemployed people or children in some really poverty-stricken areas like most of Africa, and which somehow have free Internet access. But right now, with surging Bitcoin prices and runaway transaction fees, you wouldn't be able to withdraw whatever you might earn there. Some faucets (like freebitco.in) allowed bulk withdrawals once per week (i.e. you didn't pay the transaction fees), but I'm not sure if it is still the case, and it is certainly not the case with every faucet out there