if you want some free coins without invest your money, theres only faucets and Bitcoin/altcoins ptcs
for example btcclicks : rewards are 5 satoshis minimum but referral program is 80 % (for free membership) so without active referrals it will be long to reach the 10k (or 0.1 mBTC) to withdraw.
clixcoin and adbtc have better rewards but referral program is around 8 % (check my reviews on my site) but you will get around 200 to 400+ satoshis per day
Coinpot Faucets are good too if you don't use it yet :
https://www.wibudincome.net/reviewoncoinpotOtherwise you will need to invest some money and for many investments site, theres no guarantee you will get anything back