Thank you all for your help. I have a photo but the size is too large, trying to work out how to do it at the moment!
The plaster board joins in the ceiling are all quite obvious now, some have been painted over, some hairline, so the ceiling looks like it needs taping again possibly? But it’s the staircase crack which is worry, I’ll try and upload a photo. I can’t see anything outside, but the drive looks to have sunk as the concrete around the drain is cracked and raised. Not sure if the two are related, I’ll try and get the photo