how to convert any system date format change in dyanmically

Question

Hello

I want to Convert Date format of any system in "yyyy-mm-dd"  in c# 

 

 

if system format this like-

12/01/2019

2019/12/19

20-Feb-2016

 

etc this format Convert dynamic in  like wise"yyyy-mm-dd" 

 

please help me.