There is nothing like making money for free. All method of making money requires a lot of effort. Try and pick interest in one of the ways to earn money and do research and also ask questions to have a better understanding.
If you classify your time as a resource then technically you can't earn money on the internet for "free". But if you're just looking to do something that would earn you money without a monetary investment, then affiliate marketing is your best bet. It's hard though–finding a good network with a high enough CPM and a low enough "quota" or pay-out date to be sustainable. Even the biggest "influencers" only earn pocket money from affiliate marketing.
There are many ways of getting online money such as crypto buy and sell, sites that give survey's and will pay a good amount of money, blogging, affiliate marketingor by referral links. You will get a good amount in return.