Hi, @Menta Elise
Thank you for posting in Microsoft Q&A forum.
First, we have to ensure that our existing Configuration Manager infrastructure is compatible with Windows 11 24H2 deployments, we should upgrade our SCCM to version 2409.
Don't forget to configure Software Update Point, and make sure the Windows 11 product is enabled under Software Update Point > Products.
Then, make sure all devices meet the hardware requirements for Windows 11.
Also, it's better to have a test device collection ready for testing the 24H2 in-place upgrades.
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