Last Rites is the penultimate quest in Kingdom Come: Deliverance 2, which brings players back to the origins of their adventure. Here you will have to repeat familiar actions, but now with knowledge of the backstory of events.
Descend the stairs and ask Peter Pesetsky what happened. Follow into the courtyard and after the cutscene, repeat all the same actions that you performed in the very first story mission. First, shoot at the enemies from the fortress wall, then help at the main gate, and finally follow the commander to the side rampart.
Knock down the only ladder on the wall, then deal with the remaining enemies. Soon a cutscene will start, narrating the retreat of allies into the castle.
Next Quest: Judgement Day