For dynamically resizing text size, we can use the FittedBox widget. There are various options to fit the child widget, ex BoxFit.fitWidth, BoxFit.Height etc. The default fit is BoxFit.Contain.

Example –

FittedBox(
    fit: BoxFit.fitWidth,
    child: Text('Bacancy technology, Ahmedabad, Gujarat, india'),
),

This will change the size dynamically.

Demo code – Demo Code Link