Create D partition in Windows 10

Not sure if this is a Winclone question but… I Wincloned a Windows 10 install to a new computer and everything is running fine. Now the person actually running Windows wants to split the Windows partition and create a D drive to store some data on. He has a 700 GB partition with Windows and wants to split that without touching the Mac partition which is about 300 GB. Is it possible to do this from within Windows?

Answering my own question here. Just splitting the Windows partition in Windows did the trick.

you did it with a certain tool or with windows-functions?

Just built in Windows functions:
Make a fresh backup.
Right click on This PC in File Explorer and select Manage.
Select Disk Management.
Right click the C partition and choose Shrink volume and put in appropriate numbers and click Shrink.
After some time an Unallocated space is shown.
Right click on that space and select New simple volume.
Make selections in the next dialogues as you see fit.
The new partition should be available to you.