Android - Cloud Firestore - adding and displaying the list

I'm just learning programming in the Android and Firebase. I've learned from the Youtube tutorial how to add a task to the database and how to display it. Unfortunately, at this moment I can only add one element and only one display (I do it in TextView). Can you help me create a list that will display many elements? There are not many tutorials to Cloud Firestore.

My next goal is to edit and delete data, but first I want to learn it.

This is the code of my two fragments:

public class AddFragment extends Fragment implements View.OnClickListener{

    private static final String CEL_KEY = "Cel";
    private static final String MIEJSCE_KEY = "Miejsce";
    private static final String TAG= "TAG";

    private DocumentReference mDocRef = FirebaseFirestore.getInstance().document("goalsData/daily");

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View layout = inflater.inflate(R.layout.fragment_add_goal, container, false);

        Button saveButton = (Button)layout.findViewById(R.id.bn_save);
        saveButton.setOnClickListener(this);

        return layout;
    }

    @Override
    public void onClick(View v){
        switch (v.getId()) {
            case R.id.bn_save:
                saveGoals();
                break;
        }
    }

    public void saveGoals (){

        EditText celView = (EditText) getActivity().findViewById(R.id.et_cel);
        EditText miejsceView = (EditText) getActivity().findViewById(R.id.et_miejsce);
        String celText = celView.getText().toString();
        String miejsceText = miejsceView.getText().toString();

        if (celText.isEmpty() || miejsceText.isEmpty()) { return; }
        Map<String, Object> dataToSave = new HashMap<String, Object>();
        dataToSave.put(CEL_KEY, celText);
        dataToSave.put(MIEJSCE_KEY, miejsceText);

        mDocRef.set(dataToSave).addOnSuccessListener(new OnSuccessListener<Void>() {
            @Override
            public void onSuccess(Void aVoid) {
                Log.d(TAG, "Dokument został zapisany!");
            }
        }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Log.w(TAG, "Błąd, dokument nie został zapisany.", e);
            }
        });

    }

}

Display:

public class DailyFragment extends Fragment implements View.OnClickListener{

    private static final String CEL_KEY = "Cel";
    private static final String MIEJSCE_KEY = "Miejsce";
    private static final String TAG= "TAG";

    private DocumentReference mDocRef = FirebaseFirestore.getInstance().document("goalsData/daily");

    TextView wszystkieCele;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        View layout = inflater.inflate(R.layout.fragment_daily, container, false);

        Button fetchButton = (Button)layout.findViewById(R.id.bn_fetch);
        fetchButton.setOnClickListener(this);
        wszystkieCele = (TextView) layout.findViewById(R.id.tv_goals);

        return layout;
    }

    @Override
    public void onStart(){
        super.onStart();
        mDocRef.addSnapshotListener((new EventListener<DocumentSnapshot>() {
            @Override
            public void onEvent(DocumentSnapshot documentSnapshot, FirebaseFirestoreException e) {
                if(documentSnapshot.exists()){
                    String celText = documentSnapshot.getString(CEL_KEY);
                    String miejsceText = documentSnapshot.getString(MIEJSCE_KEY);
                    wszystkieCele.setText(getString(R.string.cel_wynik, celText, miejsceText));
                } else if (e != null){
                    Log.w(TAG, "Wyjątek!, e");
                }
            }
        }));
    }


    @Override
    public void onClick(View v){
        switch (v.getId()) {
            case R.id.bn_fetch:
                fetchQuote(v);
                break;
        }
    }

    public void fetchQuote (View view){
        mDocRef.get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
            @Override
            public void onSuccess(DocumentSnapshot documentSnapshot) {
                if(documentSnapshot.exists()){
                    String celText = documentSnapshot.getString(CEL_KEY);
                    String miejsceText = documentSnapshot.getString(MIEJSCE_KEY);
                    wszystkieCele.setText(getString(R.string.cel_wynik, celText, miejsceText));
                }
            }
        });
    }

}