Don't use canned filling!
Honestly, it only takes a few minutes longer (plus cooking time) to make pumpkin pie from scratch, and it will taste so much better and be cheaper too.
But don't use carving pumpkins
The pumpkins they sell at Halloween for jack o'lanterns are bred to make good jack o'lanterns and not to be good to eat. You want a pie pumpkin. If you can't find a pie pumpkin, use a couple of butternut squashes - those are widely available in grocery stores, and cheap.
How to make pumpkin pie:
Preheat the oven to 400 F. Cut the pumpkin or squashes in half, using a serrated knife (a bread knife). Use a large spoon to scoop out the seeds and stringy parts and compost them (or save the seeds to roast if you like roasted pumpkin seeds, which I don't). Put the halves in the oven, cut side up, and leave them there for an hour or until they are soft and a little caramelized (browned) at the edges. Then take them out and let them cool for about half an hour.
Meanwhile, make the pie crust. In a medium-size mixing bowl, melt 1/3 of a cup of butter (most of a stick) in the microwave. Add 1 cup of flour, and mix. Turn the dough into a pie pan and spread it out with your fingers to cover the bottom and sides of the pie pan.
When the cooked pumpkins are cool enough to handle, preheat the oven to 400 F again. Use a serving spoon or a knife to scoop all of the cooked pumpkin or squash out of the shell. This is the hardest part. Take your time. Put all the cooked pumpkin into a bowl and mash it with a potato masher or an immersion blender. Add one cup of sugar, a pinch of kosher salt, and 1/4 cup of some mixture of pumpkin pie spices like ginger, cinnamon, allspice, nutmeg, and cloves. I often add a teaspoon of cumin or curry powder too, or some Chinese five-spice, to make the taste more interesting.
Mix and add three eggs and a cup of full-fat Greek yogurt, and mix again. Pour the filling into your pie crust and bake for about an hour, or until a knife stuck into the center of the pie comes out clean and not covered with glop. Serve warm or cold, with whipped cream or without.
Vegetarian or vegan
Pumpkin pie is vegetarian, but it's not vegan. If you want it vegan, use olive oil in the crust instead of butter, but the crust will be more crumbly. And, you'll need to use an egg substitute for the eggs.