var value by remember { mutableStateOf(TextFieldValue("")) }

OutlinedTextField(
    modifier = Modifier.fillMaxWidth(0.8f),
    value = value,
    onValueChange = { value = it }, label = {
        Box(
            modifier = Modifier
                .fillMaxWidth()
                .height(10.dp)
                .background(Color.Yellow)
        ) {}
    }
)