MainActivity.kt
override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        setSupportActionBar(toolbar)

        start.setOnClickListener {
            val intent = Intent(this, Card::class.java);
            startActivity(intent);
        }
    }

Card.kt
override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_card)
        next.setOnClickListener{
            if (checkbox1.isChecked){
                text.text = "dog"
            }
        }
    }

activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.widget.LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:weightSum="10"
    tools:context=".MainActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:theme="@style/AppTheme.AppBarOverlay"
        android:layout_weight="1"
        android:layout_height="0dp">

        <androidx.appcompat.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </com.google.android.material.appbar.AppBarLayout>

    <ScrollView
        android:layout_width="match_parent"
        android:layout_weight="8"
        android:layout_height="0dp">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <CheckBox
                android:id="@+id/checkbox1"
                android:text="@string/checkbox1"
                android:layout_width="match_parent"
                android:layout_height="35dp"/>

//dalsi checkboxy

        </LinearLayout>
    </ScrollView>

    <Button
        android:id="@+id/start"
        android:text="@string/start"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:theme="@style/AppTheme.AppBarOverlay"
        android:layout_weight="1"/>

</android.widget.LinearLayout>

activity_card.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Card">

    <TextView
        android:id="@+id/text"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:text="cat"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="160dp"
        app:layout_constraintBottom_toBottomOf="parent"
        android:orientation="horizontal"
        android:weightSum="3">

        <Button
            android:id="@+id/known"
            android:layout_width="150dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/ic_check_black_24dp"/>

        <Button
            android:id="@+id/show"
            android:layout_width="150dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/ic_cached_black_24dp"/>

        <Button
            android:id="@+id/next"
            android:layout_width="150dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@drawable/ic_arrow_forward_black_24dp"/>

    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>