If you have a nice idea and digital content to offer online, you can make decent money online.I suggest you to read this:
If you are a student/educator you can earn by answering questions. For more please read this:
Or if you have some special skills and services to offer online, you can be freelancer. You can earn in your part time with freelancing. Please read :
Explore the above options.
I hope it helpful for you! Good luck!