Hi, @Alberto IG
Thank you for posting in Microsoft Q&A forum.
We can manually download the prerequisite files on any computer with Internet connection and use it during SCCM setup.
You may follow this article for the details:
https://www.prajwaldesai.com/download-sccm-prerequisite-files-offline/
The latest baseline version of SCCM is 2203, it recommended to download it from here:
https://www.microsoft.com/en-us/evalcenter/download-microsoft-endpoint-configuration-manager
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