'Newtonsoft.Json.Linq.JArray' does not contain a definition for 'Linhaorg' [closed]

So, I created a notepad and I'm reading it through System.IO and I'm reading the file with Json , however it presents this error whenever I execute, what do I do?

Json

{
    'barreiras':
    [
        {
            'Linhaorg':1, 
            'colunaorg':1,
            'altura':2,
            'largura':1
        },
        {
            'Linhaorg':6,
            'colunaorg':3,
            'altura':1,
            'largura':2
        }
    ]
}

Code

System.IO.StreamReader file = new System.IO.StreamReader(@"pasta do arquivo");

string f = file.ReadLine();
file.Close();
dynamic stuff = JsonConvert.DeserializeObject(f);

int linhaa = stuff.barreiras.Linhaorg;
int colunaa = stuff.barreiras.colunaorg;