npm run build react setup?

Question

npm

There is the following project structure:


With the npm run build command - an error
The command is launched in the root of the project (folder react flt.by), in the same folder the following package.json

{
  "name": "FLT",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "node index.js",
    "server": "nodemon server.js",
    "client": "cd client && npm run start",
    "dev": "concurrently --kill-others-on-fail \"npm run server\" \"npm run client\"",
    "main_sectionku-postbuild": "cd client && npm install && npm install --only=dev --no-shrinkwrap && npm run build"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "aos": "^2.3.4",
    "body-parser": "^1.19.0",
    "concurrently": "^4.1.0",
    "express": "^4.17.1",
    "nodemailer": "^6.2.1",
    "nodemon": "^1.19.1",
    "react-addons-css-transition-group": "^15.6.2",
    "react-loading-skeleton": "^1.1.2",
    "react-skroll": "^0.7.2",
    "react-transition-group": "^4.1.0"
  }
}

How to build a project?

Answer 1

Do you see the build script in the list of scripts? Me neither.
Ask the one who wrote it and did not finish it.