@Tuấn Anh, Thanks for posting in Q&A. From your description, I know you want to know some download links for office and have questions with windows.
Based on my researching, you can follow the steps in the following link to download the office files you want:
For the repartition steps, I find the following link for the reference:
https://technastic.com/partition-c-drive-in-windows-10-11/
Note non-Microsoft link, just for the reference.
As "windows 365 Business" support, we help on the issue with Windows 365 Business cloud PC. For your issues, we are not familiar. if the above information still can't address your questions. You can open new threads to involve the related support to get more help. For office issue, you can open case in Microsoft 365 forum to get more help:
For windows repartition issue, you can add tag "Windows 10" , "Windows 11" or "Windows server" to get correct support.
Thanks for your understanding and have a nice day!
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