How to receive data sended from a client on tcp

Hi

I'm new to Wireshark so be easy with me, I have an exe application (TCP Client) that sends some source of data (packet I guess),

What I want is to get this packet, in this case my TCP Server translate it like this: (in C#)

            // On Receive fucntion
            CryptHelper.XorData(base._bufferSegment.Buffer.Array, num + 3, (long) (num2 - 4), this.Locale, Locale.Any);
            PacketIn packet = new PacketIn(base._bufferSegment, 7, num2 - 8, this.IsGameServerConnection);
            PacketMgr.Instance.HandlePacket(this, packet);

So how can I know what is and what type of (packet/other data) is my TCP client sending to my TCP server using Wireshark ?

Thanks in Advance.