Here is the code
using File = System.IO.File;
namespace Demo;
class Program
{
public async static Task Main(string[] args)
{
string fileToWriteTo = "myimage.jpg";
string urlImage = "https://g7y6h3a7.rocketcdn.me/wp-content/uploads/2020/03/dummy-image-square.jpg";
using var httpClient = new HttpClient();
await using var input = await httpClient.GetStreamAsync(urlImage);
using Stream streamToWriteTo = File.Open(fileToWriteTo, FileMode.Create);
await input.CopyToAsync(streamToWriteTo);
}
}