port 3000 should be open for front end, port 5000 for back end.
apt install curl
curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.1/install.sh | bash
# the following operation are done in the front_end package of source code
nvm install 16
nvm alias default 16
npm install -g npm@8
cd front_end
npm install
npm start
cd back_end
npm install
node server.js