Hi Constance, So glad you have joined our collaborative, one-world family WikiTree!
Please read through our information pages about GedCom imports. Also, please keep in mind that there is only one leaf/profile on the WikiTree for each person in the world. If two or more profiles are created for the same person, they must be merged into the first (lowest ID number) for the set of duplicates. This creates a good deal of extra work, so please minimize duplications as much as possible. (I think this is what Jillaine was mentioning about the 200 year old profiles.)
You can pretty well depend that surnames like Boone (2158 in the WikiTree database), Morgan (8355), Nichols (4693), and Coffey (1971) are going to be well represented here already. You should start by searching for the names of your earliest ancestors to see if they already have a leaf/profile on the WikiTree.