Dear saurabh Mishra 

There are lots of online business are available.One of the best platforms to make money is online.So there are ample opportunity available in Online

1.Blogger 

You can work as a blogger so that you can make money by advertising etc....

2.Product selling 

There are number of online shopping sites where you can sell products and can make money.

3.Social media manager

If you are good user of social media and if you have right skills you can earn money in online by managing social media accounts of companies actors ect

4.online tutor 

There are number of websites for online educational and you can also work as a educator and make money from your home via online

Best of luck

You can start You business By signing up as a seller on Amazon It provides a great opportunity to those who want to sell Items but don't have a good platform of other reasons. Apart from that, there are many sites where You can sell a product without purchasing them in Real. Shopify and Mojo are some names which operate on this Model.  You can also hire some people to write promotional content for some companies which will pay You for writing about their Products. You can also start Online service companies which offer service online.