If I am going to be honest, to start earning money as a teenager, without any knowledge or investment, there is no get rich quick scheme. It's simply not possible.
I have myself as a teenager recently started making my own good money and I have a few tips that YOU can take in account for yourself. As I said, you're not going to be a millonaire in a week. But this is something to get going.
Method #1: Make Money Through Cracked.io
To start making money through cracked, I would recommend you just to get your reputation up. Be an active member in the community, contribue to it and just be active in shoutbox. You can start posting threads in for example the "Hiring" section and ask if someone needs a worker, or look if someone elses thread matches your needs. This is actually how I started making money on cracked. You can also start a type of shop, try starting a shop for something you like and already have some knowledge with, for example if you play alot of minecraft, you could start an minecraft alt shop. Another easy way to get started could be e-whoring. There are alot of free guides on here and also free packs. This is an easy way to actually start making some money without any inital investment.
Method #2: Reselling
When you have made some money through cracked or any other way online, or maybe you just have an investment already, you can start reselling. You can go through the whitehat way, and go to wholesaling sites like Fleek and buy vintage items, you can sell them on apps like Depop or Vinted. I have done this before and actually made me a quick buck. You can also go through the more greyhat way and sell for example replicas or vapes, replicas you can find from alot of places. You have probably heard of Pandabuy since it recently blew up, or you could find a private supplier through Cracked or other forums.
As I said this isn't some get rich quick scheme, but I shared my personal experience.
Enjoy!