The correct grade is shown in the user's handbook, but there are so many different engines listed that there's a risk of choosing the wrong one (as I did once).
If you go onto the Euro Car Parts website and key in your car's registration mark then it should bring up the correct grade. It didn't used to but it does now.
FYI, this is what I'll be buying today for my wife's V60 D3 with the VEA engine.
https://www.eurocarparts.com/p/mobil...w-20-521779262
This is the correct grade, i.e. 0w/20 made to Volvo's specification.
Our two "VEA" Volvos also tell us how much oil to put in. Does yours?