Nikon D780 DSLR Camera (Body Only) - Manual (Page 703)

657 Menu Guide > B The Setup Menu
Frequently-used combinations of settings can be assigned to
the
U1 and U2 positions on the mode dial ( 0 115).
Reset settings for U1 and U2 to default values ( 0 118).
Choose a language for camera menus and messages. The
languages available vary with the country or region in which the
camera was originally purchased.
Save User Settings
G button
U B setup menu
Reset User Settings
G button
U B setup menu
Language
G button
U B setup menu