If you use the official Mastodon app, or an instance that has disabled it - you are unable to see the Federated timeline, which is why you would only see the Local timeline - IE things the people on your instance are sharing or following.
The federated timeline is a chronological stream of everything. A bit fast, but kinda magical in a way because I discover so many people just by spending 10-15 minutes combing through it during my visit each day.
I’ve also started following the same celebs/orgs that I used to follow on other social media.
And most importantly, I control what I see - not some algorithm funneling me into a partisan view of the world, which is a massive part of the issue with Twitter and Facebook and their relationship to current political situations.