Since you know nothing about "how to make money online" this makes you a beginner and as such I recommend you 2 methods.
#1 Affiliate marketing (create a blog or a website recommended) find some affiliate program that is easy and has high commissions and use to earn money by drying traffic to their landing page.
#2 PPC marketing (pay per click) this method allows you to make money for free! Create YouTube account and verify it to enable monetization. Then from there apply for Adsense. Once you get your Adsense account approved upload your videos and enable ads on them. If your videos are cool and get a ton of views you will make decent amount of money.
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