//Text in Button
TextButton(
  onPressed: ()=>{}, 
  child: const Text("Signout")
),

//Text button with icon
TextButton.icon(
  label: Text('Signout'),
  icon: Icon(Icons.logout),
  onPressed: () {}
),

//Text button with filled background
TextButton(
  child: Text("button"),
  style: TextButton.styleFrom(
    primary: Colors.white,  //Text Color
    backgroundColor: Colors.teal, //Button Background Color
  ),
  onPressed: () {},
),