I'm guessing everyone on the same relays can see it, but I'm not that aware of how the backend of Nostr works 😅

Some people only look at the people they follow, and only follow me people based on those people sharing other people's posts, or other people commenting on posts.

I hang out on the global feed, so I see new people all the time.

Writing things that are high value seem to get more attention.

These are some of my thoughts to your question.