Follow
@maison_faim@mstdn.social
The Home feed is supposed to be for people, accounts you follow.
I think these other posts you see are replies or mentioning the account you do follow.
@maison_faim@mstdn.social that screenshot quote was taken from a new guide to mastodon that is still being built.
A bit more detailed, but if you want and have time to read, it's online here: https://rame.altervista.org/mastostart/
I would say that's not a beginner's guide, but a mid level one.