main:
  var connection = new SSHConnection(host, username, password);
string text = await connection.ReadStream();

Console.WriteLine(text);
connection.WriteStream("ls");
text = await connection.ReadStream();
Console.WriteLine(text);

Console.ReadLine();


classes:

class SSHConnection : IDisposable{
    private string _host;
    private string _username;
    private string _password;
    private StreamWriter _writer;
    private StreamReader _reader;
    //private MemoryStream _memory = new ();
    private String _lastcommand;
    private SshClient _client;
    private ShellStream _shellStream;
    
    public SSHConnection(string host, string username, string password){
        _client = new SshClient(host, username, password);
        _client.Connect();
        if(!_client.IsConnected) throw new Exception("Client not connected.");
        
        var terminalModes = new Dictionary<TerminalModes, uint>();
        terminalModes[TerminalModes.TTY_OP_ISPEED] = 0x00009600;
        terminalModes[TerminalModes.TTY_OP_OSPEED] = 0x00009600;
        _shellStream = _client.CreateShellStream("xterm", 80, 24, 800, 600, 1024,terminalModes);
        
       
        _writer = new StreamWriter(_shellStream) {AutoFlush = true};
        _reader = new StreamReader(_shellStream);
        
        
    }

    public async Task<string> ReadStream(){
        var buffer = new char[4096];
        var read = await _reader.ReadAsync(buffer, 0, buffer.Length);
        var input = new string(buffer, 0, read);
        return input;
        
    }
    
    public void WriteStream(string command){
        while (_shellStream.Length == 0)
            Thread.Sleep(500);
        _writer.WriteLine(command);
        _writer.Flush();
        _lastcommand = command;
    }
    
    public void Dispose(){
        _writer.Dispose();
        _reader.Dispose();
        _client.Disconnect();
        _client.Dispose();
    }
    
    
}

main:
  var connection = new SSHConnection(host, username, password);
string text = await connection.ReadStream();

Console.WriteLine(text);
connection.WriteStream("ls");
text = await connection.ReadStream();
Console.WriteLine(text);

Console.ReadLine();


classes:

class SSHConnection : IDisposable{
    private string _host;
    private string _username;
    private string _password;
    private StreamWriter _writer;
    private StreamReader _reader;
    //private MemoryStream _memory = new ();
    private String _lastcommand;
    private SshClient _client;
    private ShellStream _shellStream;
    
    public SSHConnection(string host, string username, string password){
        _client = new SshClient(host, username, password);
        _client.Connect();
        if(!_client.IsConnected) throw new Exception("Client not connected.");
        
        var terminalModes = new Dictionary<TerminalModes, uint>();
        terminalModes[TerminalModes.TTY_OP_ISPEED] = 0x00009600;
        terminalModes[TerminalModes.TTY_OP_OSPEED] = 0x00009600;
        _shellStream = _client.CreateShellStream("xterm", 80, 24, 800, 600, 1024,terminalModes);
        
       
        _writer = new StreamWriter(_shellStream) {AutoFlush = true};
        _reader = new StreamReader(_shellStream);
        
        
    }

    public async Task<string> ReadStream(){
        var buffer = new char[4096];
        var read = await _reader.ReadAsync(buffer, 0, buffer.Length);
        var input = new string(buffer, 0, read);
        return input;
        
    }
    
    public void WriteStream(string command){
        while (_shellStream.Length == 0)
            Thread.Sleep(500);
        _writer.WriteLine(command);
        _writer.Flush();
        _lastcommand = command;
    }
    
    public void Dispose(){
        _writer.Dispose();
        _reader.Dispose();
        _client.Disconnect();
        _client.Dispose();
    }
    
    
}