Hi, @Duchemin, Dominique
Thank you for posting in Microsoft Q&A forum.
Yes, it is possible to upgrade directly from Configuration Manager 2203 to Configuration Manager 2303, you do not need to install all the intermediate versions.
We can upgrade to version 2303 directly from version 2111 or later.
However, before upgrading, it is recommended that you review the release notes and checklist for each version to ensure that your environment meets the requirements for the new version and to understand the changes included in each update.
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