The update for Kingdoms in the works is not massive according to the information available but will fix at best some oversights of kingdoms campaign features that are broken (i.e. the game was unfinished and not properly tested) It will not fix anything for M2TW. Also, there has been no updates on it for several months, meaning that it might not even come out at all.

Thus 1 is there is no patch.
2 the patches for kingdoms are installed automatically when you got it (1.2 + 1.3)
3 You can check that Kingdoms is properly installed if it runs on your machine.