I’m not exactly sure how I did it, but I think I just ticked off NSFW in my profile.

As far as I know you can block individual accounts from appearing in your home and public timelines. It’s important to notice that what you see depends on which instance you’re logged in, since the owners can moderate the content and maybe “defederate” other instances.

You can take a look at https://pixelfed.org/servers to check the list of servers available (or run your own!)