You have a $20 bill, and you need to double it. You have 1 month, you must keep it in cash (No banks, cashapp, credit cards), you don’t have an address, a phone number, or and you can’t interact to people in public. using just the internet and an email, how do you double the money?
100% return in one month? Just using the internet? Impossible.
That’s one of those things that would be immediately, completely used up the moment it exists. A free lunch, basically.
In theory, you could get a few percent annualised return for nothing the conventional investment way, but I don’t know how easy that would be especially with a small amount, and anti-laundering laws exist to (try to) stop you from doing it anonymously like that.
It feels like you might be hoping for a hustle, but you either need to deliver something of value right at the time of the transaction, or promise to deliver value and have an verifiable identity where they can come and find you if you don’t. Because the other people with the money you want aren’t stupid.