You can use veeam community edition or Veeam Backup Essentials (paid version - VUL) for scenario 1 and 2. 

Agent Backup:

https://helpcenter.veeam.com/docs/backup/agents/introduction.html?ver=110
 

NAS Backup:

https://helpcenter.veeam.com/docs/backup/vsphere/file_share_support.html?ver=110

Community Edition:

https://www.veeam.com/virtual-machine-backup-solution-free.html

Veeam do not have a solution for Android Devices

I’m not aware of any platforms that backup/restore the entire device for Android, so the focus tends to be on app data, services such as Office 365 can be protected by Veeam, but any built in photo apps etc aren’t going to be protected. I’d suggest getting people to save their important data to cloud services and focusing on protecting the cloud services themselves.

This is what you need to check.  And as noted no Android backup capabilities.

All what I am aware of for Android backups are some apps. But in order for most of these to function you have to root your phone.

Not the ideal solution I think.

To copy your important data to a cloud service and backup it from there, is the much better way to do this.

I agree with @Mildur and @MicoolPaul : use VBR and Veeam Agent for your Windows 10 clients and network drive. Try to use built-in backup functionalities on Android devices to the cloud and if possible use backup functionalities to backup your cloud-services.

I am not aware of any backup solution for Android. But in Android 12 there seems to be some kind of virtualization included. Maybe this this will open up some new opportunities for backup-software vendors.