It's easy to get any place name, cemetery or other division smaller than what is currently in the database, "accepted as a standardized place in Family Tree." You just type in the complete name then click on the top, grey line in the drop down menu that is exactly what you just typed, then make sure the standardized version which will be one or more divisions up, is correct. If it is not, then click on the standardized version and pick the correct one.. The place name will then look like this in the editing box:
This is correctly entered and correctly standardized and is how Family Tree has been designed to work since it opened.
Ron Tanner discusses this in his Feb. 13, 2020, Q&A video starting about 39:00.
This is a valuable function in Family Tree because you can nearly always add additional place information more specific than what is in the places database:
For my complete explanation of this topic, you can go through this presentation I put together (it is purely my view, with no involvement of anyone at FamilySearch):
Now, having said all that, I suspect what your question really is, is "how do I get the cemetery that my parents are buried in" added to the place name database?
FamilySearch is continually working to improve the place name database and as part of that is gradually adding in cemeteries and places of worship and they do accept suggestions for ones that are missing. The easiest thing to do is to post the request on the FamilySearch Places group here in this community. It is located here:
As you scroll through the posting, you will see they get a lot of requests so it might take some time to get the cemetery you want added. In the meantime, do be sure to correctly enter the full name as outlined above.
Lets see who from FS will answer this.
I am also interested in the answer - its the same question for any location that goes beyond the city level . . .