I urge you to get a copy of a very basic cookbook, such as Betty
Crocker, and follow the directions for apple pie. What you are doing
is mixing TWO fillings together -- the one from a can, and the other
"from scratch" but missing some ingredients. What you describe
probably doesn't taste very good! When you make fruit pie from scratch
you will need to pay attention to what variety of fruit you use -- some
has more juice, some has more tartness, some gets mushy, etc. This is
particularly important with apples! A cookbook will explain all that.