Can't connect to my local database on Visual Studio : I created a local database inside visual studio it self (1st time that I've done like that)

I got the following code:

> SqlConnection conn = new SqlConnection(@"Data Source=DESKTOP-50MFBOD\Hugo; Initial Catalog=Database_AvaliacaoConnectionString1; Integrated Security=true");
SqlCommand cmd = new SqlCommand();

When I click the insert button, it doesn't insert the data into my GridView and it pops up this error:
[Image][1]


  [1]: https://i.stack.imgur.com/YE7Jv.png