Hi Gwenael,
For setting up simple meetings I have attached a detailed article on how you can use the Access portals to set up the process. However, in case you still don't see the options mentioned in the article please reach out to your account manager as "Simple Meetings" is a feature that has to be enabled for the account. And there could a possibility that it is not enabled for your account because of which you are unable to see the options.
Simple Meetings Configuration Guide
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Anurag Sindhu
Senior Client Success Advisor
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