Websites like Commaful and Storybird are specifically designed for posting short stories. They offer user-friendly interfaces and communities of fellow writers who can provide feedback and support.
Websites like FictionPress or Archive of Our Own (AO3) could be great. FictionPress is specifically for fiction, and AO3 has a wide range of fanfiction and original works. Both have active user bases and supportive communities.
Well, you might look into platforms such as Archive of Our Own (AO3), which is great for various types of stories. Or, if you prefer a more professional setup, try pitching to literary magazines' online editions. Some well-known ones include The New Yorker and The Atlantic. Just make sure to read their submission guidelines first!