If they don't tell how to do it, they are of no use for you.
Some might be thrustworthy, others might not. See if you can find reviews or contact other members. If they let you pay before you can earn anything, it's suspect. If they only pay in crypto, it's suspect also.
I'm a one-year-old daughter's mom, moms always have to stay at home to take care of the baby, so do I. So I will find out some ways to make money online, and I found cashback site can let you make money by referrals, which similar to affiliate program. How I earn money fast and do they deserve faith?