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Does anyone know a tutorial that teaches me how to code them in C++? I want to learn how to make my program send packets and recieve them.

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Two different tasks are usually meant by "send packets" — normal socket I/O (TCP/UDP) and crafting/injecting raw frames (custom IP/TCP/UDP headers or Ethernet frames). Start with the basics, then move to low-level tools only if you really need them.

Begin with simple socket programs: a UDP echo and a TCP client/server so the concepts socket, bind, connect, listen, accept, send and recv are clear. Remember platform differences: POSIX sockets on Linux/macOS vs WinSock on Windows (WSAStartup, closesocket vs close). For C++ style async I/O and portability, consider Boost.Asio once the basics are comfortable. As suggested, a good sockets tutorial will get those fundamentals quickly.

If the goal is to craft or capture packets (faking headers, sending raw Ethernet frames, sniffing traffic), use packet libraries rather than only standard sockets. On Unix/Linux you can use raw sockets or the AF_PACKET interface for link-layer frames; on Windows, link-layer work generally uses a pcap-style driver (Npcap/WinPcap historically). These operations require elevated privileges (root/Administrator). Libraries like libpcap for capture and libnet/pcap injection for packet construction simplify many low-level details (checksums, framing).

Practical cautions and troubleshooting: firewalls and OS policies often block or filter traffic; check firewall rules and port bindings first. NIC offloading can hide checksum/length differences in captures — disable offloads when debugging. Test in an isolated lab (VMs or a private LAN) to avoid legal or network policy issues. Use packet analyzers (tcpdump/wireshark) to verify what actually hits the wire. If packets do not appear, check interface selection, privileges, and whether the kernel or NIC is altering packets (or rejecting malformed packets).

As noted, read focused FAQs and hands-on guides after the basics. A short learning path is: learn sockets, write simple client/server, inspect with Wireshark, then try pcap-based capture/injection or raw sockets with careful attention to permissions and OS limits.

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