Q.strawberry plants in container
My plant has brown edges on the leaves all of a sudden. Even the berry starts are turning brown. It was very hot lately. They are in full sun 12 hours. I water regularly.

The heat is getting to your strawberries. Brown edges mean the plant is stressed and it probably needs extra water and some shade if your weather has been very hot.
This article may help you:
https://www.gardeningknowhow.com/edible/fruits/strawberry/container-grown-strawberries.htm