Home, when used as a verb and often followed by "in on," means to head towards a destination, like your home — although you can home in on any place.
Homing pigeons, when released from their coop, fly to a spot they've been taught to home in on. Likewise, guided missiles home in on their targets. Home in can describe the act of getting closer to something you want, of narrowing a search or nearing a goal, and even the act of reaching or achieving that goal.
These examples show how home in can be used to describe either a journey in progress or the arrival at a final decision or place:
General manager Billy Eppler said Monday at baseball's winter meetings that he has homed in on six to seven potential targets, including two on the trading block. (Los Angeles Times)
There's also a lack of geographic focus; whereas Kubrick homed in on the Overlook and pretty much stayed there, Flanagan's film is all over the place, crossing restively from state to state. (The New Yorker)
To hone something means to sharpen it. It usually refers to a blade, but can also be used metaphorically to mean improving at something, like honing your skills by practicing the clarinet. This notion of pointed focus explains why people sometimes confuse these verbs. But hone is not typically followed by a preposition; you hone a blade, but you don't hone in on it.
You can see in the examples below how common this error is, appearing in publications where editors should know better:
The team honed in on the gut microbes and found 12 species that seemed to exist in much higher or lower numbers in the diseased mice. (BBC)
Notably, he honed in on two things that make social ads unique: their speed, and the way they can target small niche communities at scale. (The Verge)
Hone your language skills by learning how to use home in correctly. To use this phrase correctly just think of a homing pigeon returning to a specific location.