This reads like a plot summary, which is not necessary since the plot summary is located on the story pages in question.
After Davros was getting ill and old, he grew weak and was put into the infirmary to help him as the life-support attached to his wheelchair began to slowly disfunction and wear out.
While he was there he began to remember his childhood and having met and been saved from Handmines by the Twelfth Doctor. He sent Colony Sarff out to search and tell him that he was anticipating their final meeting.
When the Doctor arrived in the infirmary Davros told him that an old man should die where his children are and showed the Doctor their conversations on blue screens on the walls. Davros made the Doctor watch Clara Oswald and Missy be exterminated and his TARDIS destroyed from the infirmary. (TV: The Magician's Apprentice)
The Doctor threatened Davros to get out or he would be killed. He threw Davros out of his wheelchair and left him on the floor to die, leaving in his wheelchair, until a Dalek found him and helped him as Sarff attacked the Doctor, bringing Davros his wheelchair back.
Davros brought the Doctor the only other chair on Skaro as he spoke about the cables in the room connecting him to every Dalek on the planet. The Doctor told Davros that Gallifrey and his people were back in the sky, hidden away, to which Davros congratulated him on his success, crying and asking to look at the Doctor with his own eyes.
The Doctor gave Davros a chance to see the sunlight with his own eyes, owing the little boy from the battlefield on last favor. As Davros said he was unable to open his eyes, the Doctor broke open a vein in his hand, starting up some regeneration energy and powered the cables, giving Davros new prolonged life and renewed all Daleks on Skaro.
As the delaying Daleks in the sewers gained this new life as well and began to take revenge on their abandoners, the Doctor fled the infirmary as it began to crumble down on Davros. (TV: The Witch's Familiar)