To simplify the Modernize template, I created a new Next.js project and then modified it by copying files/code from Modernize. I installed only the libraries/dependencies (latest versions at the date) required by this simplified project. Here's how I did it:


npx create-next-app@latest 
npx create-next-app@14.2.5
✔ What is your project named? … nextjs-test
✔ Would you like to use TypeScript? … No / Yes
✔ Would you like to use ESLint? … No / Yes
✔ Would you like to use Tailwind CSS? … No / Yes
✔ Would you like to use `src/` directory? … No / Yes
✔ Would you like to use App Router? (recommended) … No / Yes
✔ Would you like to customize the default import alias (@/*)? … No / Yes
✔ What import alias would you like configured? … @/*


This are the libreries needed:
npm install @mui/material 
npm install @@emotion/react 
npm install @@emotion/styled
npm install @mui/material-nextjs
npm install @mui/icons-material

npm install react-apexcharts @tabler/icons-react

npm install react-redux
npm install --save-dev @types/react-redux
npm install redux-persist
npm install @reduxjs/toolkit

npm install axios
npm install axios axios-mock-adapter
npm install --save-dev @types/axios

npm install simplebar-react simplebar

npm install lodash
npm install --save-dev @types/lodash

npm install chance
npm install --save-dev @types/chance

npm install react-i18next i18next
npm install --save-dev @types/react-i18next

npm install stylis-plugin-rtl

npm install date-fns

npm install react-slick slick-carousel
npm install --save-dev @types/react-slick

npm install framer-motion

npm install react-intersection-observer


Delete
src/app/page.tsx
src/app/page.module.css
src/app/globals.css


public/ tiene que ser reemplazada por la correspondiente de Modernize. En public/ están todas las imágenes usadas.


We need to create:
package.json
package-lock.json
.env
src/app/app.tsx
src/app/globals.css


Estas también están en Modernize. Aún no sé para que sirven así que no las he creado:
src/app/loading.tsx
src/app/not-found.tsx


npm install


I have created/edited the following folders/files and files based on https://www.youtube.com/watch?v=g566eI2EmeY
src/app/layout.tsx
src/app/(DashboardLayout)/layout.tsx
src/app/auth/auth-context/AuthContext.js
src/app/components/protected-route/ProtectedRoute.js
src/app/auth/authForms/AuthLogin.tsx
src/app/auth/authForms/AuthRegister.tsx
src/app/(DashboardLayout)/layout/vertical/header/Profile.tsx
src/app/(DashboardLayout)/layout/vertical/header/data.ts
src/app/(DashboardLayout)/layout/vertical/sidebar/Sidebar.tsx
src/app/(DashboardLayout)/layout/vertical/sidebar/SidebarItems.tsx
src/app/(DashboardLayout)/layout/vertical/sidebar/MenuItems.ts
src/app/(DashboardLayout)/layout/vertical/header/Navigation.tsx
src/app/(DashboardLayout)/layout/vertical/header/AppLinks.tsx
src/app/(DashboardLayout)/layout/vertical/header/QuickLinks.tsx
src/app/(DashboardLayout)/layout/vertical/header/data.ts




To run the NextJS app:  
npm run dev
npm run dev -- -p 3000 


If case we want o unistall packages:
npm uninstall @mui/material


To recreated node_module:
rm -rf node_modules
rm package-lock.json (only in some particular cases)
npm install




Notas:
package-lock.json:
    Records the exact dependency tree that was installed: Exact versions (no ranges), Exact sub-dependencies, Resolved URLs, Integrity hashes
    So, when you run npm install: npm does not guess - npm recreates the same tree every time.
    So, package-lock.json exists to: Prevent dependency chaos, Make builds reproducible, Save you from random breakage