AuthContext.js

import {createContext, useState} from "react";

export const AuthContext = createContext()

export const AuthProvider = ({children}) => {
    const [user, setUser] = useState({})
    return <AuthContext.Provider value={[user, setUser]}>
        {children}
    </AuthContext.Provider>
}

login.js

import {Auth} from 'aws-amplify';
import {useContext, useEffect} from 'react'
import {useState} from 'react';
import {useForm} from "react-hook-form";
import {useRouter} from "next/router";
import {XCircleIcon} from "@heroicons/react/solid";
import {AuthContext} from "../src/AuthContext";

export default function Login() {
    const {register, handleSubmit} = useForm();
    const router = useRouter()
    const [user, setUser] = useContext(AuthContext)
    ...
}