you can only include your spouse and dependent children (under 18 years of age) in your immigration application as accompanying family members. you cannot add your father, mother, brother, or sister at this stage. however, you can sponsor your parents once you have the immigrant visa and have landed in canada as a PR.
about the fees, the fee for adults is 550 canadian dollars and for dependent children its 150 canadian dollars. to give you an example, i am applying with my wife and three children as accompanying dependents. so total fee in my case is 1550 canadian dollars (i.e. 550 for me, 550 for my wife, 150x3=450 for three children).
hope this helps.