Microsoft provides great resources for support on their applications and services, including step-by-step instructions and video tutorials. We have added some of them here for you.
Microsoft Office 365
https://support.office.com
Delve
https://support.office.com/en-us/delve
Excel
https://support.office.com/en-us/excel
Groups
https://support.office.com/en-us/article/learn-about-office-365-groups-b565caa1-5c40-40ef-9915-60fdb2d97fa2
OneNote
https://support.office.com/en-us/onenote
Outlook
https://support.office.com/en-us/outlook
Planner
https://support.office.com/en-us/article/microsoft-planner-help-4a9a13c6-3adf-4a60-a6fc-15c0b15e16fc?ui=en-US&rs=en-US&ad=US
PowerPoint
https://support.office.com/en-us/powerpoint
Publisher
https://support.office.com/en-us/publisher
SharePoint
https://support.office.com/en-us/sharepoint
Skype for Business
https://support.office.com/en-us/skype-for-business
Sway
https://support.office.com/en-us/sway
Teams
https://support.office.com/en-us/teams
To-Do
https://support.office.com/en-us/article/welcome-to-microsoft-to-do-762cbbf9-7fc1-48e5-b619-005622da89d0
Word
https://support.office.com/en-us/word
Yammer
https://support.office.com/en-us/yammer