On Samsung's version of Pie, called One UI, notifications on the lockscreen stay minimized. You can change it to go back to the normal way of showing full notifications by going to "Settings -> Lock Screen -> Notifications (tap the word notifications) -> View Style = Detailed. Also turn off "hide content".
As others have mentioned, turn on Always On Display as well. Settings -> Lock Screen -> Always on display
There's no notification light on the 10 series of phones like previous samsung phones