People have passed away, where to bury them?

If it's in Shenzhen, in my opinion, there's no need to bury them; direct sea burial is fine, and there's a 3,000 yuan subsidy available.
Actually, by the time they pass, it's probably unrealistic to find a cemetery. Most likely, only sea burials and tree burials will be options because there are no more burial plots available.
Currently, there are only about 3,000 operational cemeteries left in Shenzhen, while the number of deaths each year exceeds 15k.
At the current rate of consumption, in just a few years, there will be no more space. Shenzhen is unlikely to add new land for cemeteries either.
Sea burial is quite good; anyway, now the 80s and 90s generation don't have much of a tradition of being buried in the ground.