I advise you to visit this place. To get from the center of Istanbul, you need to take a public or private ferry from Kabatazh Pier and get to Buyukada Island (on Adalar). You'll have to climb the hill a bit there. But the unforgettable beautiful view of the sea from the highest point of the island is worth it. There's a restaurant nearby. There is a place to eat and drink drinks.
We were in a Greek Orthodox monastery for the first time. Very impressive!!! A quiet place! A beautiful view of the ascent to the monastery. You can put candles and pray.