Flutter - Bottom Overflowed By 119 Pixels

put your contents in a SingleChildScrollView and add ConstrainedBox like this:

body :SingleChildScrollView(
        child: ConstrainedBox(
          constraints: BoxConstraints(),
            child: ListView(
         children:<Widget> [
           new Container(
             child: new Stack(
               children:<Widget> [
                 //THE WIDGET
                 new Container(), //THE BACKGROND IMAGE
                 new Positioned(
                   child: Column(
                     children:<Widget>[
                         new Transform(),
                         new FadeTransition(),
                         new FadeTransition(),
                         Divider(),
                         new Row(),
                         //THE IMAGE THAT I WANT TO ADD
                         new Container(
                           height: 360.0
                           decoration: BoxDecoration(
                            image: DecorationImage(
                               image: Assetimage('lake.jpg)

This is may make your screen scrollable and adding constraint will make it finite scroll.

Nothing, Just include your widget inside Expanded like this

 Expanded(
    child: sectionList(),
  )

//this solved my issue

Use Scaffold property "resizeToAvoidBottomPadding: false" and "SingleChildScrollView" as parent of Scaffold body:

    home: Scaffold(
          resizeToAvoidBottomInset : false,
          appBar: AppBar(
            title: Text("Registration Page"),
          ),
          body: SingleChildScrollView(
            child: RegisterUserPage(),
          )),