Id saying learning to develop websites or learning designs skills might be a good way to earn money.
Plenty of free resources online, freecodecamp.com is one id recommend they help you learn then teach you how to get jobs.
This is also recommended by my friend who is also a freelance web designer and i have also joined web designing course for that,and i am still learning about it.I hope it will help me also to make some money online after i learnt that skill of designing and development also.
Well best of luck on your journey to learning more.
Even if its not for money it helps to understand what your using in your daily life it could even lead to a different job at the job one might already have.