From what I can tell Bluesky doesn't have an algorithm. It just seems to show you the posts/reposts from the people you follow in chronological order.
If you don't like those, anyone can develop a feed algorithm and anyone can subscribe to it, so you can have topic based feeds like "Science" or you can have feeds that just change the way the feed behaves like "OnlyPosts", which is the following feed but with no reposts or replies.