You don't see ADD buttons because you haven't processed your suggested matches. The yellow-highlighted entries in the right-hand column are suggested matches that haven't been marked yet. Every one of them needs to be marked as MATCH or REJECT before ADD buttons will appear on the main Gedcompare page.
However, if you go to a person (such as yourself) that is in your Gedcom and is matched to a profile in WikiTree, and open the COMPARE screen for that person, if there are no unprocessed suggested matches for immediate family members, you should see ADD buttons next to the person's immediate family members who aren't already in WikiTree. Click on one of those ADD buttons to see how GEDCOMpare is supposed to work -- and add that person. I always recommend that people work from a COMPARE screen like that one (where possible) to add people to WikiTree, since it helps ensure that the connections in your Gedcom will be preserved.
PS - I see that you've manually added some profiles since you asked this question. If these people are also in your Gedcom, be careful that you don't add them again!