Check out example codes for "container border radius flutter". It will help you in understanding the concepts better.

Code Example 1

Container(
  child: Text(
    'This is a Container',
    textScaleFactor: 2,
    style: TextStyle(color: Colors.black),
  ),
  decoration: BoxDecoration(
    borderRadius: BorderRadius.circular(10),
    color: Colors.white,
    boxShadow: [
      BoxShadow(color: Colors.green, spreadRadius: 3),
    ],
  ),
  height: 50,
),

Code Example 2

Container(
      child: Text(
          'This is a Container',
          textScaleFactor: 2,
          style: TextStyle(color: Colors.black),
      ),

      decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(10),
          color: Colors.white,
          border: Border(
              left: BorderSide(
                  color: Colors.green,
                  width: 3,
              ),
            ),
          ),
      height: 50,
     ),

Code Example 3

Container(
  child: Text("It's text..."),
  decoration: BoxDecoration(
    borderRadius: BorderRadius.circular(10),  // radius of 10
    color: Colors.green  // green as background color
  )
)

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