Can you use the properties of any QUAD to proove another property of that same quad QUAD?

so i'm given parallelogram ABCD.( the set up is this: A is the top left vertex and continue going clockwise.) The image shows diagonal AC and BD. i need to prove that AC and BD bisect eachother. keep in mind that i am allready reading an example given from the book. So the example uses a property of parallelograms...... which is that opposite sides of a parallelogram are congruent.... to PROVE a property of paralellograms... which is that diagonals bisect eachother. Is the purpose of this problem to use properties of a parallelogram to proove another property of the parallelogram...? ijust want to make sure that this is what we are doing and that i'm on the right track........ and so can i use the properties of any quadrilateral to proove a property.. or anything else about the SAME quadrilateral??????