I’m in the tropics, so I get tropical fruit all year around. I freeze pineapple all the time. Just peel it, core it, chop it, or slice it and freeze it in a Ziploc bag or in any plastic container. It’s excellent to make smoothies or just plain juice. Put it in the blender, half OJ and half pineapple. As @rooeytoo says the texture changes and frozen fruit is no longer good to eat in a fruit salad, but great to bake and for smoothies.
Other tropical fruits that freeze well are mangoes, guavas, and papaya/papaw. Passion fruit also freezes beautifully.
As for veggies I freeze carrots, corn, green beans, and green peas. I blanch them then freeze them in Ziploc bags, then use for soups, rice, pasta, salads you name it. They freeze very well. Also sweet peppers, I seed them and cut them in quarters (never whole).