Michael, welcome to WikiTree.
You're just one more step to become a Wiki Genealogist. Please see the following help page:
"A Family Member can become a Wiki Genalogist at any time by signing the Wiki Genealogist Honor Code."
Our community mission is to create one accurate single family tree that's free and open to the world.
The help pages and G2G are great resources to learn how to collaborate in our mission.
Profiles for your father and grandfather were already created as can be seen in the answers to this other post:
The merge of the duplicate profiles has been proposed. For more information on "Merging" see here:
There's information on your great-grandparents with sources in the 2nd. answer, so you can grow the family tree.
Welcome aboard once again, Michael