Can you put a 1970 front grill and bumpers on 1969 dodge dart?

No, you can't directly bolt on a 1970 Dodge Dart grille and bumpers to a 1969 Dodge Dart. While they might look similar, there are significant differences in the bodywork where these parts mount. The mounting points, dimensions, and even the shape of the body itself are different enough to make it a major, likely impossible, modification without extensive custom fabrication.