Personally, I like Biscuits on top of my chicken pot pies ( no bottom crust). That being said, Puff Paste works really well as a pie topper, and you can roll it thinner and use to line the pie pan first, if you want a bottom crust as well. Filo dough, I don't use except to make those little spinach/ cheese appetizers that are folded into triangles and brushed with melted butter before baking. I would buy both filo and puff paste pre made. ( I don't use either very often). In US, these products are in the freezer section of a grocery store.
As far as biscuits go, you can either make rolled out biscuits or drop the dough on top by the spoonful. Biscuit dough should be mixed lightly just until the dough holds together, then rolled out, again using light motions with the rolling pin. If making "drop" biscuits, add a bit more liquid than recipe calls for, and spoon it onto the top of whatever you are baking. If using biscuits on top of a chicken pot pie, have the pot pie ingredients hot and bubbling before placing the biscuits on top. This helps the undersides of the biscuits cook. Otherwise, they can turn out kind of soggy on the bottoms.
To make a decent pie crust use very cold butter/ fat/ lard cut into bits before working it into the flour mix. Crumble it with your fingers and then add very cold water one tablespoon at a time. Once it holds together, Shape it into a ball or two balls. Wrap and refrigerate 30 minutes before rolling it out on a lightly floured surface. When rolling out a pie crust, lightly flour the rolling pin, the work surface and the top of the dough ball. With the palm of your hand, Flatten it slightly, then from the Center roll it a little, give the dough a quarter turn sideways and roll again. Keep rolling and turning until it is all rolled out. (Turn the dough to the other side when it is about half rolled out). Then carefully roll it up loosely and transfer to the pie pan. If it tears, it is easily patched together by pressing the dough lightly with the fingers.
Type in YouTube dot com and in the search, put in Pie Crust.
Yes, you can use refrigerated ( store bought) biscuits successfully for Pigs in blankets too. If you are able to buy refrigerated biscuits, the store probaly has already made pie crusts too. The ingredients in biscuits or pie crust should not be too expensive, so it is worthwhile to experiment and attempt to make either one. Filo dough and puff pastry, can be a little more expensive, plus you have to find out if they are available where you live.
I say, give it a go and make a pie crust.