Rules for trained at club/trained in nation

I bought at dutch player from Parma to Juventus. When I'm looking at his status in Parma it says he will become trained at club later the same year, but when I get the player there is no date for trained in nation.

Do the player have to stay at Parma until he gets trained at club for him to become trained in nation for me?

Or are there different rules for trained at club and trained in nation so that a player who is trained at club for one team doesn't necessary become trained in nation for other clubs in the same nation?

Is this a bug, or are the rules this way in real life?