Living in Eretz Yisroel, if one can do it, is definitely a good thing, but whether it’s an actual mitzvah depends on a machlokes Rambam and Ramban. The Ramban holds that the mitzvah of living in Eretz Yisroel applies at all times. But the Rambam holds that it was a one-time command to the generation who came in with Yehoshua and does not apply nowadays; nowadays it’s only a desirable thing, but not itself a mitzvah.
However there is one thing everyone agrees on: A Jew may never consider chutz lo’oretz his home. Eretz Yisroel is always every Jew’s home, it’s just that most of us, for one reason or another, are currently living away from home. A person may live away from home for an extended period, whether for work, or something he has to do in some other place, or just to experience a different country; but his legal home remains the place where he intends eventually to return. That’s where he is based for taxes and voting, and for his driver’s license, and that is what the gemara means when it says that “Whoever lives in chutz lo’oretz is as if he has no G-d”. The moment a Jew says of chu”l “This is my home, I have no reason ever to leave here”, then he has become an apikores.