I don’t think there is any way you can earn free money in the crypto space. Before you can earn any money from crypto, you will have to work before you earn any crypto. If you want to earn, then there are a few ways that I know you can earn crypto, but you will have to work before you earn it.

Since you don’t have any money, which you will use to invest, then you can participate in bounty campaigns on the forum here. Actually, most of the bounties on the forum don’t really pay again,  but if you keep on participating, you might be earning a little amount from it.

You can also participate in testnet airdrops, actually, not all will pay, and some won’t pay well, and you will need to have patience because you might participate in some airdrop for a year or more before paying.

If you have any skills, then just visit the service board, you can display your skills there, and anyone who needs your service will slide into your DM. Those are some of the ways that I know you can earn crypto without investing.