So, you will have to decide how to carry the tile around the pass through opening where there are the gaps between the cabinet and the opening. On that wall I would suggest keeping the tile at the undercabinet height, then it dies into the window opening and you need to be clever with trim pieces. In this scenario, start the wall tiling in alignment with the left side of the left upper cabinet -- the tile follows the cabinet.

OR you could do only a short backsplash, just up to the bottom of the pass through opening. This is usually done with the counter material but could be cute with tile. There is a photo in here

https://www.houzz.com/magazine/try-a-shorter-kitchen-backsplash-for-budget-friendly-style-stsetivw-vs~8498300 of one made of a single row of square tiles. In this scenario, tile all along the length of the counter, the tile follows the counter.