It is real, but it is not free money out of nowhere
Cashback is genuine. But the money comes from somewhere: the marketing budgets of the shops. They pay to win customers, and you get a share of that payment. No magic, just a model.
It will not make you rich
Cashback is not a source of income. It is a way to get a little back on spending you have anyway. Anyone promising you wealth from cashback is overselling it.
The trap is shopping more
The only way cashback can cost you money is if it tempts you into buying things you do not need. Buy the same as before, and you always come out ahead.
