You can use Microsoft Graph SDK for Javascript which provides various features to enhance working with all Microsoft Graph Services with less complexity. You can find the steps to follow, code snippets and how to use the library over here. Basically, you need to register your application in Azure AD and provide necessary Microsoft Graph permissions to the registered application to perform various graph operations.
This page also provides few samples and tutorials to start with.
Additionally, you can refer to the documentation here to learn more on using REST for Outlook API.