First I got "Error: Server responded with status code 403" when i tried to print the statusCode.

Adding headers like 'User-Agent' and 'Accept' helps the server accept your request and respond with the data you expect.( i told chatgpt to give me headers )

var response = await http.get(
                Uri.parse("https://jsonplaceholder.typicode.com/posts"),
                headers: {
                  'User-Agent': 'Mozilla/5.0',
                  'Accept': 'application/json',
                },
              );