I am looking for a guided tour in English to the Last supper and the Santa Maria delle grazie
The venue offers guided tours in English to visit the Last Supper. I did one in 2022 and the guide was marvelous. We did not go into the church of Santa Maria della Grazie, though but it was open and you could go visit.
When you book your ticket (a trial in and of itself) book from the official venue's booking website and you will see the times of the guided tour so book that choice.