1) YouTube: Becoming a youtuber is easy and quick however you will need to work hard as competition is tough and you will need some genuinely good ideas to get subscribers. You get paid on YouTube based on the number of ads you run on your website.
2) Blog: Decide you niche. Are you a lifestyle blogger or a food blogger? Make people follow your blog on social media sites and than monetize it.
3) Start your online business: You can start an online food business or a clothing business, this one really depends on what skills you have and what resources are you willing to spare.
4) E-books: Selling E-books is another good way but again competition is quite tough.
5) ad posting: Some websites and online businesses pay you for posting ads, if you are committed in this you can do it however, it requires patience as the amount is low.
6) Making courses on udemy: making professional courses on demanding subjects like finance, personal development and IT can help you especially if a lot of people start taking it.
7) Freelance writing on fiverr, freelancer, upwork etc. There are tons of freelance websites looking for remote workers.
8) Remote Graphic designer on various freelance sites, graphic designing is a highly skilled profession and there are plenty of positions available.
9) Developer: Many sites pay developers and programmers a lot. If you have studied IT you can easily earn online.
10) WordPress developers: Learn how to make wordpress sites and installation, there are plenty of positions available in that area too.