Problems with xml in different sizes of screens [duplicated]

Good afternoon, I can not understand how it does the compatibility of several screen sizes in my application, I looked on the internet and on youtube and there to create a folder inside res with the name layout-small if it would be for small screen sizes but an error appears in my xml and I can not run the application ... Can anyone help me?

<ImageViewandroid:id="@+id/imageView4"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="102dp"
    android:layout_alignParentTop="true"
    android:layout_alignParentStart="true" />
<Button android:id="@+id/button2" android:layout_width="match_parent"
    android:layout_height="wrap_content" android:text="Button" />