You can read our guide to What is a TPM? And here's why you need it for Windows 11 for an in-depth rundown of what these modules do and how to find out if you have one, but in a nutshell: TPM 2.0 support is required by Windows 11, and though many laptops and PCs sold in the past few years already have it, it may be disabled by default.
Microsoft has some pretty steep system requirements for this version of Windows, most notably the demand that your PC have a TPM (Trusted Platform Module) 2.0 installed. Before we dig into whether you should upgrade to Windows 11, it's important to verify whether you can.