There are many ways to earn crypto free without invest or mining.
The popular is Airdrop but i think the best way to earn is Bounty.
Most of newbie always try Airdrop than Bounty.
It's obvious that newbies prefer airdrops more than bounties. One airdrop doesn't take much time: you only have to fill a form, join some chat or group. And then just wait for an airdrop. Forum bounty campaigns require high rank to get a sufficient reward. Also, almost every bounty takes about 2-3 months to finish it and get a reward. After that you have to wait for a listing to sell your tokens.