Which one is right Intune Device Group or User Group

Hi oryxway390, 

You are asking two questions. Which group should be used to assign configuration profiles to and which membership type should be used? Hopefully, I can answer both questions.

Let's start with user or device groups, If you want to apply settings on a device, regardless of who’s signed in, then assign your profiles to a devices group. Use device groups when you don’t care who’s signed in on the device, or if anyone is signed in. You want your settings to always be on the device.

And use user groups when you want that your settings to be applied to a specific user, whatever device they use. 

for more information: Assign device profiles in Microsoft Intune | Microsoft Docs

So hopefully this helps you with which group you will assign to your profiles. By default all almost all groups are static, If you are creating a new group, it is be default assigned. You must always manually add the user or device to the group. This can be very time consuming by adding the user or device each time you have a new device or user. So you can use Dynamic group based on rules and the groups will be automatically populated. 

Rules for dynamically populated groups membership - Azure AD - Microsoft Entra | Microsoft Docs

so based on how you decide to make/build your configuration you can choose, which type of group to assign

Kind regards,

Rene