Pumpkin and squash can be used interchangeably in most recipes without a noticeable difference. Here are some tips and links for cooking pumpkins and squash, all of which make great breads, pies, soups, muffins and more.
Step one is to make the puree, by cutting the pumpkin or squash in half cleaning out the insides by removing the seeds and stringy flesh (save the seeds and bake or sautee them for a delicious snack). Turn the halves upside down or cut into smaller pieces and place in a baking dish with a bit of water in the bottom to keep them from drying out. Bake at 375 degrees Farenheit for 1½ to 2 hours for a small pumpkin. Then scoop out the flesh which should be soft and mushy and mash it or puree it in a blender or food processor. Now you can substitute that in any pumpkin pie recipe where it calls for canned pumpkin pie filling.