How to create tabs screen of a web browser?

I try to create a simple web browser. I need help to create a tabs activity.

How to show a preview of web-view? Is this preview is an image?

I take a bitmap from web-view in this way:

    Thread {
        if (binding.webviewMain.width > 0 && binding.webviewMain.height > 0) {
            val bitmap = GlideBitmapPool.getBitmap(
                    binding.webviewMain.width,
                    binding.webviewMain.width,
                    Bitmap.Config.RGB_565)
            val canvas = Canvas(bitmap)
            binding.webviewMain.draw(canvas)
            if (!directoryTabs.exists())
                directoryTabs.mkdir()
            val fName = "IMG_${positionPage}_tabs.JPEG"
            val file = File(directoryTabs, fName)
            try {
                val fos = FileOutputStream(file)
                bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos)
                fos.flush()
                fos.close()
            } catch (e: Exception) {
                e.stackTrace
            }
            //Recycler Bitmap
            GlideBitmapPool.putBitmap(bitmap)
        }
    }.start()

But, Is this way is correct? Thank you for helping me.