How to deploy React app with docker and serve -s build - reactjs

Question

So far I have build the image and deployed it to AWS EC2. But I want to use
serve -s build
to serve the app in production mode.
I did it locally and apparently everything seems to be fine..I get this..
┌──────────────────────────────────────────────────┐
│ │
│ Serving! │
│ │
│ - Local: http://localhost:5000 │
│ - On Your Network: http://192.168.1.91:5000 │
│ │
│ Copied local address to clipboard! │
│ │
└──────────────────────────────────────────────────┘
And the page enters..but the when I try to make a request to the api I get 404.
I wanted to know how does react build works and what do I need to do to put it in production mode. And also, what is the dist folder for?
This is my Dockerfile:
FROM node
#Create app directory
WORKDIR /app
# A wildcard is used to ensure both package.json AND package-lock.json are copied
# where available (npm#5+)
COPY package*.json ./
#Install dependencies
RUN npm install
RUN npm install react-scripts#3.4.1 -g --silent
#Copy app's source code inside the Docker image
COPY . .
#Expose the app's port
EXPOSE 3000
#Run the app when the container is ran
CMD ["npm", "start""]
Thanks!

Answer 1

This is my Dockerfile I use when I run it with serve -s build
# pull official base image
FROM node:13.12.0-alpine
# set working directory
WORKDIR /app
# Copies package.json and package-lock.json to Docker environment
COPY package*.json ./
# Installs all node packages
RUN npm install
# Copies everything over to Docker environment
COPY . .
# Build for production.
RUN npm run build --production
# Install `serve` to run the application.
RUN npm install -g serve
# Uses port which is used by the actual application
EXPOSE 5000
# Run application
#CMD [ "npm", "start" ]
CMD serve -s build
I just switch between npm start (debug) and serve (for production).