There are a huge number of platforms available to post your work on as an artist, and many of them are saturated with artists. If you’re just getting started with posting your art, I recommend choosing 2-3 platforms that you will regularly post on. Try to figure out which one feels most intuitive and enjoyable to you and make that one your area of focus. You can get the most out of a platform when you understand how it works and what kind of content works best there, which is something you learn by using it. I personally use instagram the most, but I find it to be quite oversaturated and difficult for newer artists to get noticed there. Twitter also has a great artist community. If you are finding it difficult to get your work seen on bigger platforms, try joining smaller communities, like forums or discord servers. In general, I recommend posting on a few different platforms to cover your bases, but don’t spread yourself too thin.