@uoou Hello fellow single-user admin!
My advice is to open a few interesting instances and click into their local timelines. If you see any users who look interesting, then open their profiles and copy the URLs. Then, you can paste them into the search box of your own instance and follow them. Once you've followed a few people from different instances, your federated timeline will start to populate. Then you can look for other interesting people, follow them, and repeat until you've reached a level of content that you're happy with.
Don't feel nervous about following and boosting! That's how content spreads in the #fediverse. Use hashtags! If you have general questions, then tag #mastodon or #fediverse. #MastoAdmin is great if you have questions about running your instance.
PS - once you get used to mastodon, I recommend trying a fork like glitch-soc. Forks offer fancy features like markdown, better filters, quote boosts, longer posts, and UI tweaks.