Bitcoin faucet's totally free and probably that what you meant for, but that's not literally free, you need to collect with the specific time depend on the sites.  AFAIK, Freebitco.in gambling site was still has that faucet feature as of now but the problem is the minimum amount of withdrawal is quite high and it might take years for you before you can transfer into your wallet.

I tend to agree above, there's no someone who willing to give free Bitcoin without any reason or any return because Bitcoin is a sort of money that has value.

A Bitcoin wallet that you have control of your key and Electrum wallet might you need for free.