Generally, if you want to camp in the cemetery, they require that you buy a plot of at least 50X100. You have to perk it, too, to make sure there is enough water to live and to assure that a septic system will have enough space to take care of waste. I think they frown on Port-a-potties.
Your tent will have to blend into the background so as not to offend the eyes of other mourners. You will not be allowed to stay there if you wear a path through the grass. You will have to take a different route to your tent every time you come back.
Food will be a problem. You’ll only be able to eat prepared foods. No cooking on site. It’s not just the fire concerns, but the smells tend to offend the residents.
Who are another problem. They are accustomed to taking strolls at night while their coffins are aired out. Unfortunately, the dead are a rather dull bunch, and they never vary their routines. You will have to expect them to stumble through your tent at all hours of the night. Not exactly the kind of party mates you might want.
All in all, I would suggest you do not pursue this course of action, except, of course, if you are dead, yourself. But then, why would you need a tent?