It sounds a very big ask .. but would be easier if it were broken down into manageable asks, with full details of what you already have.
So - whose occupation do you want to know? Have you find that person on a census (if after 1841) or on a baptism of their child (if before) where an occupation may be recorded?
When it comes to graves, first you need to find a death (if after 1837), then a burial. Or just a burial in a Parish register if before. A burial does not mean there will be a headstone though.
As to how long "they" lived in the area, that will be a case normal thorough research, taking each person at a time and working back one step at a time, confirming each step from as many different sources as possible.