Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Office normally won't uninstall like that. Are you sure that you didn't just lose one or more shortcuts that open the apps? In that case, you can search for Word (for example) from the Windows Start menu and then pin shortcuts to the taskbar and/or Start menu. If you did in fact lose the apps, that might have happened following an Online Repair. You can reinstall via your associated account at https://account.microsoft.com/services .