Where can I find Expense Tool trainings and guides ?

Expense Tool training videos, FAQs and Guides are available on the Expense@Microsoft Training Sharepoint Site.

Use the "Expense Tools" drop down link at the top of the sharepoint site to navigate between the available training materials for all expense tools at Microsoft.

You will only have access to create or submit expense reports in tool enabled for your country/business group
https://microsoft.sharepoint.com/teams/ExpenseAtMicrosoft