I can’t perform most operations over npm, like downloading packages

I want to learn backend using node.js on my computer but the npm command is not working. When I say it’s not working, I mean I want to install a file and it doesn’t give any errors but I can’t use the packages.

npm i cors

up to date, audited 852 packages in 6s

found 0 vulnerabilities

Also it’s packet.json

{
  "name": "deneme",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo "Error: no test specified" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "cors": "*",
    "express": "*",
    "nodemon": "*"
  }
}

It doesn’t show in the versions after installation

const express = require('express')

const app = express()

app.listen(4000 , () => {
    console.log('hello');
})

node deneme.js
node:internal/modules/cjs/loader:1145
  throw err;
  ^

Error: Cannot find module 'express'
Require stack:
- C:*******Desktopdenemedeneme.js
    at Module._resolveFilename (node:internal/modules/cjs/loader:1142:15)
    at Module._load (node:internal/modules/cjs/loader:983:27)
    at Module.require (node:internal/modules/cjs/loader:1230:19)
    at require (node:internal/modules/helpers:179:18)
    at Object.<anonymous> (C:*******Desktopdenemedeneme.js:1:17)
    at Module._compile (node:internal/modules/cjs/loader:1368:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1426:10)
    at Module.load (node:internal/modules/cjs/loader:1205:32)
    at Module._load (node:internal/modules/cjs/loader:1021:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:142:12) {
  code: 'MODULE_NOT_FOUND',

Tried Solutions:
-Tried different npm versions.
-Checked the PATH variable.
-Ran commands as administrator.
-Cleared the npm cache (I cant because its not working )

Does anyone know the reason for the issue and how to fix it?

I tried to download ‘npm i cors’ and other packages, but it didn’t work. Something is blocking it, but I couldn’t solve it. I already provided the details above