AAVE or something else to earn 3% interest on fiat money?

AAVE seems to be offering 3% interest on USDC. Is this legit? How should someone go about doing this? Do I have to buy ETH and transfer it to a wallet, exchange it for USDT or USDC, etc.? Also, is there some other DeFi network like AAVE you’d recommend?

Confluent Mozambique Aug 19, 2021

Blockfi and celcius offer 8%

Synopsys scoped OP Aug 19, 2021

You have a referral code?

Synopsys scoped OP Aug 19, 2021

Also what’s the catch with these providing 2x interest compared to AAVE? Do these carry more risk?