Usually, you would crack open the router login and add some port (e.g 54984) to the port forwarding menu, but since it’s kinda hard to do so, here’s an easier way, that involes a phone and a USB cable plus whatever windows machine or mac you are currently using for scambaiting
First, you need to have a phone or tablet running ANDROID 5.1+, then, you need a micro-usb, mini-usb or type-c usb charging cable, (even C-to-C chargers should work), then you need to install this modded PdaNet+ APK that I can verify works best for scambaiting, link to google drive: https://drive.google.com/file/d/10Mt9J7fVyb7QqLTgvN7tpJoKYUq04f4D/view?usp=drivesdk, now you need to download the setup file for your windows PC, you need to head over to PdaNet+'s website: Download PdaNet+, after you download the setup, run it and it will require you to plug in your android device to install ADB drivers, (YOU MUST HAVE DEVOLPERS MODE ON AND USB DEBUGGING ON), and you lastly need this free VPN, that has lots of open TCP/UDP ports (perfect for NanoCore, njrat, etc), https://play.google.com/store/apps/details?id=com.fast.free.unblock.thunder.vpn, then you need to turn on USB mode and allow the Computer to connect to the “ethernet” and you can even use the phone or tablet as a storage device even while PdaNet+ is running with the VPN going through it