As fronnt is nothing but a Node.js app, you can control it with PM2
pm2 start index.js
See PM2 docs for more information.
Create a Dockerfile with the following content
# Base image
FROM node:16-alpine
# Set working directory
WORKDIR /usr/src/app
# Copy package.json and package-lock.json
COPY package*.json ./
# Install production dependencies
RUN npm ci --only=production
# Copy app code
# (assuming all your app code is located in a src directory)
COPY ./src/* .
# Set NODE_ENV=production
ENV NODE_ENV production
# Expose port 4000 (which is the default)
EXPOSE 4000
# Run app
CMD [ "node", "./index.js" ]
docker build . yourname/fronnt
docker run --name=my-fronnt-app -p 4000:4000 yourname/fronnt