Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello Ekooo
To cover the easy questions first
#1 - OneDrive - anyone has access to a free 5gb OneDrive account whether or not they have any version of Office installed. If you have a subscription then you also get a 1TB Onedrive account
#2 - OneNote - is available to anyone - it's free
https://www.onenote.com/download
As for the benefits of one version of Office over another - the following show what is available with Office 2019 Home & Business and Office 2019 Home & Student
Office Home & Business 2019
https://www.microsoft.com/en-us/microsoft-365/p...
Office Home & Student 2019
https://www.microsoft.com/en-us/microsoft-365/p...
and you can compare the differences between H&S vs a subscription to MS 365 here
https://www.microsoft.com/en-us/microsoft-365/b...
Key differences between a retail (one-time purchase) license and a subscription
Subscription
#1 - A premium Outlook.com account
#2 - A 1TB OneDrive account
#3 - Always the latest version
#4 - Can be installed on all your devices
Retail
#1 - Can only be used by one user/one computer
#2 - No upgrade options to newer versions
#3 - Office H&S doesn't include Outlook and other various apps