Auth0JS vs NextJS SDK

Greetings,

I am developing a NextJS app and my final choice for impleenting authentication is Auth0, this is what I find most practical.
My question though is, if I want to return an access token after the user logs into the website, then i will need to use the Auth0-js package and write my own custom code for the login/signup pages?

I need the access token to further develop a custom API i want to use on my backend.