Every one of those fruits has a pile of seeds in it, kinda scattered randomly through it. Mash the apple up and pick the seeds out. They will have to be stratified (go through a cold period) to break the seed dormancy so they'll germinate. Either put the seeds with a little moist sand in a ziplock in the fridge/freezer for a couple months and sow 'em in the spring, or sow them in flats/small pots outside about February or so to let them get some cold weather. After they start growing and get a few leaves on them, transplant them into one-gallon pots. Feed them with Osmocote or a similar slow-release fertilizer.The next year or whenever they start getting rootbound move 'em up into 3 or 5 gallon pots. After they get 3-4 feet tall or so, plant 'em in the ground. Osage grows pretty quick, you should have small bow-sized trees in ten years or so if you plant them in a good spot.