Becoming a web or a graphic designer is a solid way to earn an income online whilst doing something creative.

As a web designer you'll be working on projects which deal with how people interact with a digital service/app/website.  If you are a graphic designer you'll be dealing with brand assets and logos - ensuring that a company is visually represented in the way they want.

Usually a web designer will also be able to code to a basic level where as a graphic designer will not code.  Both jobs are similar and there is a lot of crossover.

Finding work is a lot easier as a web designer and especially as a UI/UX designer - working on software design.

Learning to design is a unique path.  Most people will simply start designing because they like doing it or think they will but others will take an online course.

Sites like Udemy offer excellent courses for starting designers such as the UI/UX design course  and the Graphic Design masterclass are excellent starting points.

Finding clients will be the hardest part of your job.  Once you've got the skills and a portfolio it's time to start trying to sell your skills to companies all around the world.

The good news is that designers are in high demand.  Not anywhere near as high as developers - but they are certainly high in demand.  If you have the skills and portfolio - getting clients should be simple.  But in reality it's the part people struggle with most of all.  

Taking an online course like the MasterClass will enable you to start winning decent paying contracts from day 1.  Learning how to win projects and clients is just as important as design skills.