Hi. I am new to this program. Is there a way to upload your own content? Also animations? If not. This is definitelly a suggestion!
You mean in a game you make? You can package a game and its assets as a ZIP archive and upload the whole thing to Itch. Many engines do it for you nowadays, or you can do it with tools like 7-Zip. It has a GUI, at least on Windows. And in Linux you can use something like XArchiver.