Halloween (Hallowed Evening) is a Catholic tradition. In the past, people would celebrate the vigils of feasts much more than we do now. So the night before All Saint’s day, families would go out to clean and decorate the graves of their loved ones (since those loved ones were hoped to be in heaven and therefore some of the “all saints”). Traditions grew into things like scaring away the devil with masks, preparing special foods and treats for that evening’s dinner, etc. Catholics are generally a party-happy bunch.
Obviously through many twists and turns, this morphed over the centuries into the American practice of kids going door-to-door for candy. There is nothing wrong with that part - except the dentist bills.
This problems today are that any chance to dress-up over the age of about 8 has become a chance to be “sexy”. Halloween parties for teens and adults are usually bad news, not because of Halloween but because of the secular culture.
And those folks who think they really are ‘witches’ and those who just like to get a rise out of the puritan-leaning Christians have adopted Halloween as a satanistic event. That is not the origin, but both sides (the witches and the puritans/evangelicals) get a lot of play out of that.
So to really celebrate, go out to a cemetery to tidy up and then have all your friends and neighbors over for a big dinner and lots of dessert.