How to make list view builder scrollable and set its height space as much as it can take?

I have a problem with ListView. I need to make it scrollable and set its size to max space it can take. Below listView I have a button that should be visible, but the ListView covers it. I tried solutions from similar topics:

• put ListView into SingleChildScrollView
• make ListView Expanded

So the problem is:

• how to make this listView scrollable?
• how can I set its size to max as it can take (I mean it should be between 'List of participants' and Leave button)
• how can I attach this button to be always on the bottom of screen, no matter what size of screen I have?

I hope pictures help you to understand what I mean. I also add the code but it is formatted weird, so sorry about that.

Screenshoot from device with above problem:

How it looks on another device and how it should look:

Widget build(BuildContext context) {
    return Scaffold(
        resizeToAvoidBottomInset: false,
        appBar: AppBar(
          title: const Text('Flutter SDK'),
          centerTitle: true),
        body: Padding(
            padding: const EdgeInsets.all(16),
            child: !isInitializedList
                ? Column(
                    children: [
                      TextField(
                        controller: usernameController,
                        readOnly: true),
                      const SizedBox(height: 12),
                      TextField(
                        decoration: const InputDecoration(hintText: 'Conference name'),
                        controller: conferenceNameController),
                      const SizedBox(height: 12),
                      ElevatedButton(
                        onPressed: () async {
                          // Step 5: Call joinConference()
                          await joinConference();
                        },
                        child: isJoining
                            ? const Text('Joining...')
                            : const Text('Join the conference')),
                      const Divider(thickness: 2),
                      const Text("Join the conference to see the list of participants.")
                    ],
                  )
                : Column(
                    children: [
                      Text(
                          'Conference name: ${conferenceNameController.text}',
                          style: const TextStyle(fontWeight: FontWeight.w400, fontSize: 16)),
                      const SizedBox(height: 16),
                      Column(
                        children: [
                          const Align(
                              alignment: Alignment.centerLeft,
                              child: Text(
                                  'List of participants:',
                                  style: TextStyle(color: Colors.blue, fontWeight: FontWeight.w600))),
                        const SizedBox(height: 16),

                        // Step 7: Display the list of participants
                          ListView.separated(
                            separatorBuilder: (BuildContext context, int index) {
                              return const SizedBox(height: 5);
                            },
                            shrinkWrap: true,
                            itemCount: participants.length,
                            itemBuilder: (context, index) {
                              var participant = participants[index];
                              return Padding(
                                padding: const EdgeInsets.all(4),
                                child: Row(children: [
                                  Expanded(
                                    flex: 1,
                                    child: SizedBox(
                                        height: 150,
                                        width: 150,
                                        child: VideoView.withMediaStream(
                                            participant: participant,
                                            mediaStream: participant.streams?.firstWhereOrNull((s) =>
                                                    s.type == MediaStreamType.camera),
                                            key: ValueKey('video_view_tile_${participant.id}'))),
                                  ),
                                  Expanded(
                                    flex: 1,
                                    child: Padding(
                                      padding: const EdgeInsets.symmetric(horizontal: 8.0),
                                      child: Column(
                                          mainAxisAlignment:
                                              MainAxisAlignment.center,
                                          children: [
                                            Text(
                                                "${participant.info?.name.toString()}"),
                                            Text(
                                                "status: ${participant.status?.name}")
                                          ]),
                                    ),
                                  )
                                ]),
                              );
                            }),
                    ]),
                    const SizedBox(height: 16),
                  ElevatedButton(
                    style: ElevatedButton.styleFrom(primary: Colors.red),
                    onPressed: () async {
                      // Step 6: Call leaveConference()
                      await leaveConference();
                    },
                    child: isJoining
                        ? const Text('Leaving...')
                        : const Text('Leave the conference'))
                ])
        )
    );
  }