The only comment I’d add here is that you should make sure you have a real domain, that you’ve paid actual money to, when setting this up. ActivityPub assumes the domain is immutable, and the free dynamic domain names you can get (or free TLDs like, say, .ml was) are a bad choice. Spend the $10 or whatever, because if something happens to your domain name, you cannot just update it in the database and fix federation: it completely breaks everything in a way that’s not repairable.
If you want to keep up with trending topics, find news outlets you believe provide you the proper coverage of what you’re after, and just follow the RSS feeds instead.
Mastodon/Lemmy/Reddit/Facebook/Twitter are there for people to post hot takes on the news, not just share the news. RSS is the way to go if the news is what you’re after, and not people commenting on the news.