Two weeks Japan two weeks South Korea/ help planning?

I’m flying in oct 2nd to Tokyo narita

My flight back home is November 1st Tokyo haneda

When I fly in I want to stay a couple days in narita and explore plus rest from the flight
But I also want to go to South Korea I don’t know if I should go to South Korea after two weeks in Japan and then fly back into the airport a day before my flight home and stay in Tokyo or just go from narita to South Korea and fly back in and stay two weeks in Tokyo for the flight back home

Trying to fit South Korea into my Japan trip

My flight is for one month in Japan

Is two weeks sk and two weeks Japan do able?

Or would it be too much

Or should I just do one week sk

by ApprehensiveData5399