You seem to have federal and state parks confused.
In Mn, with a permit to carry, it is legal to carry in state parks, including buildings.
No need to inform anyone.
Federal parks are subject to the state laws of the state they are in, with the additional rule of no carry in federal buildings, so outside is fine, dont go inside .
The "inform" part is for courthouse or government centers[think sherriffs office] and the state capitol.
I suggest refreshing your memory by re-reading your class handouts or textbook [you did get something from your instructor I hope].