And a warm welcome to Rootschat from me.
There are various websites which have transcripts of burial registers - some are free like FamilySearch and FreeReg. Others have user-submitted entries for individual graves such as Findagrave.
Depending on when and where your ancestors died they could have been either buried or cremated. Also, depending on their level of affluence they may have been buried but no permanent marker erected (as is the case with the majority of my ancestors).
It might be a good idea to post the name, age, date and location of the death of one or two of your ancestors on this thread and see what Rootschatters can come up with. This would give you a better idea of the websites we use which are most useful for the area/era you are searching.
Philip