I have installed mongoose but nothing changed this is showing me the same error again and again. Error: Cannot find module 'mongoose'

Require stack: -C: \Users\ keshav\ Desktop\ educationWeb\ app.js at Function.Module._resolveFilename(internal / modules / cjs / loader.js: 902: 15) at Function.Module._load(internal / modules / cjs / loader.js: 746: 27) at Module.require(internal / modules / cjs / loader.js: 974: 19) at require(internal / modules / cjs / helpers.js: 92: 18) at Object. < anonymous > (C: \Users\ keshav\ Desktop
educationWeb\ app.js: 3: 18) at Module._compile(internal / modules / cjs / loader.js: 1085: 14) at Object.Module._extensions..js(internal / modules / cjs / loader.js: 1114: 10) at Module.load(internal / modules / cjs / loader.js: 950: 32) at Function.Module._load(internal / modules / cjs / loader.js: 790: 14) at Function.executeUserEntryPoint[as runMain](internal / modules / run_main.js: 76: 12) { code: 'MODULE_NOT_FOUND', requireStack: ['C:\Users\keshav\Desktop\educationWeb\app.js'] }