APN Setting on iphone 13

I have a Huawei portable router which i have been using on my apple devices prior to upgrading to iphone 13. Now i cant connect as it says i need to make sure my APN setting says "mobiledata" and i cant find it. Tried ringing EE but they were not much help says it is built into the phone. Can anyone help with this please as i just got an eSIM and that also says my APN need to be set to "mobiledata". I cant see where i add that anywhere and it's frustrating!!