Is it a fruit or vegetable?!

The problem is mixing up culinary and scientific terminology. For scientists, the word "fruit" means a part that developed from the ovary of a flowering plant, which is considerably different from its common meaning, and includes many poisonous fruits.

Fruit (scientific): the ovary of a seed-bearing plant
Fruit (culinary): any edible part of a plant with a sweet flavor
Vegetable (culinary): any edible part of a plant with a savory flavor

So scientifically they are all fruits. Culinarily, the tomato and avocado are vegetables, and a pumpkin is usually a fruit but could really be either.

You didn't ask but I'm telling you anyway: tomatoes and pumpkins are, scientifically speaking, berries (so are bananas!), but raspberries and blackberries are not (they're compound fruits).

Botany classes, and borrowed some language from wikipedia.

They are all fruits.

Fruit has seeds on the inside, or around it someplace.
Vegetables are the edible part of the root or stem of a plant.
Fruit is the edible ovary of a plant.

Botanically fruits are anything containing a seed. One site a few days ago said cooks divide it between sweet and savory so they might not count any of those as fruits or only the pumpkin. But, they are all fruits.

All three of the produce you mentioned are FRUITS because of the seeds. Fruit has seeds.

fruit grows on trees
vegetables in the garden and root vegetables under the dirt

An avacado is a fruit. Tomatoes and pumpkins are vegetables.