On phone, so can’t type much. Please have a look at article 83: list of conditions to consider when determining the corrective measures (fines or other measures).

Also: there’s a guidance document for authorities here: https://ec.europa.eu/newsroom/just/document.cfm?doc_id=47889

EU law does not work with exact codified procedures, which I understand is more common in US. So indeed, you will find guidance but not exact procedure (though it seems to be clear enough to me)

EDIT: article 83 instead of 82