Enable experimental features: in Tools ▸ Options… ▸ LibreOffice ▸ Advanced check Enable experimental features (may be unstable).
But there is no “Options” sub-menu under the Tools menu.
Here are two screenshots to prove it. These are taken from LibreOffice 220.127.116.11.
The first is from the top level of LibreOffice before opening any documents.
The second is from Writer after creating a blank document.
Neither one of them shows “Options” under the Tools menu.
Did this feature simply not make it into the release? That would seem unlikely because the experimental ribbon interface is featured so prominently in the release notes.