Correction: I see that it is your children (not yourself) who you aim to connect to Jefferson and that you hope to connect them via Thomas Jefferson Ponder. So you would want to add your children's ancestors (father, grandparents, etc.) to the tree until you connect them to the existing profile for Mr. Ponder. (Keep your children's profiles private, but give them a "public family tree" so that they can see their connections to their ancestors and cousins -- and so you can use WikiTree's Relationship Finder to probe relationships.)
And Mr. Ponder's profile currently has no parents or other ancestors -- meaning he's not showing a blood relationship to any cousins or ancestors. That means that profiles need to be created for his parents, grandparents, etc., until you can make connections with existing profiles. Do you have records for his Mr. Ponder's parents, etc.? The profile names his parents, but you should be able to learn more by searching at familysearch.org for census records and other documents. Many members here would be happy to give you pointers on searching. Do you have names of other ancestors and relatives?
Happy hunting! If you can tell us what you are searching for, you can get more focused help.