You probably have two Hitman 2 apps installed. Don’t launch the free starter pack version which only lets you access ICA Facility and Hawke’s Bay.
If you have a physical disc then launch the game from the disc, if you bought it digitally then launch that.
Go to Library > Purchased Games > Hitman 2 > Your Add-ons, to see what locations are installed and if you have anything ready to be installed.
If the location dlcs are listed as installed then go ahead and launch your Hitman 2 Gold Edition app and you’ll have the locations playable.
All 6 locations + Himmelstein should be in Your Add-ons, either listed as installed or ready to be installed.
To download the dlcs from the Expansion Pass you need to search for their dlcs name in PS Store. So for example if you want to install the bank location then you need to type in and search “Hitman 2 - New York”.