Can you please tell how do I add assertions in my step definition file?

[shalu0628]

This is the code in my step definition for assertion --
const headingtitle = element(By.css('h2'));
let heading = await headingtitle.getText();
console.log(heading);
expect(heading).to.be.equal('First Name');
Am facing the below error

E/launcher - Error: TypeError: Cannot read property 'expect' of undefined
at Object. (C:\LenderPortal-UI\typeScript\stepdefinitions\lenderinfo.js:15:26)
at Module._compile (internal/modules/cjs/loader.js:1063:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
at Module.load (internal/modules/cjs/loader.js:928:32)
at Function.Module._load (internal/modules/cjs/loader.js:769:14)
at Module.require (internal/modules/cjs/loader.js:952:19)
at require (internal/modules/cjs/helpers.js:88:18)
at C:\LenderPortal-UI\node_modules\cucumber\lib\cli\index.js:142:42
at Array.forEach ()
at Cli.getSupportCodeLibrary (C:\LenderPortal-UI\node_modules\cucumber\lib\cli\index.js:142:22)
at C:\LenderPortal-UI\node_modules\cucumber\lib\cli\index.js:169:41
at Generator.next ()
at asyncGeneratorStep (C:\LenderPortal-UI\node_modules\cucumber\lib\cli\index.js:44:103)
at _next (C:\LenderPortal-UI\node_modules\cucumber\lib\cli\index.js:46:194)
[18:24:28] E/launcher - Process exited with error code 100