You can follow this tutorial to configure a Huawei router to connect to NordVPN using L2TP.
First things first, these changes are made in the web configuration panel of your router. You can access it by visiting the local IP of your router from your web browser. The two most common, default local IPs that most routers have are 192.168.1.1 or 192.168.0.1 – you can access these by opening http://192.168.1.1 or http://192.168.0.1 in your browser. The default IP, username and password are listed in your router’s User Manual.
Please note, that L2TP alone does not encrypt your traffic, it only reroutes you through one of our servers. Please use it at your own risk. This does not apply to L2TP/IPsec.