It seems that you've added the infobox to the profile of the person, instead of to the cemetery category.
In this case a new cemetery category needs to be created. An easy way to do that is the following:
1) Add [[Category:Category name]], so in this case [[Category:Olive Hill Baptist Church Cemetery, Hebron, Georgia]], to the person profile.To get the correct naming of the category, look at similar categories in the same area, for example here.
2) After saving you'll see a red link at the bottom of the profile to the non-existing cemetery category. If the category exists, it will be a green link.
3) Click on the red link. You'll go to the page to make this category.
4) Add the infobox template to the cemetery category, with the correct information.
5) Check for mistakes with "Show preview".
6) Save the new cemetery category. The person will now be in the cemetery category.
For adding more people to the same cemetery, you'll just need step 1, for adding additional cemeteries you'll have to repeat all steps.