A posted document number is the key to everything it created. Find Entries shows all of it on one page.
Press Ctrl+Alt+Q or choose Find Entries from a posted document, a ledger entry, or Tell Me. Enter a document number (or external document number, or a date range) and Business Central lists every table that has entries for it, with counts: posted invoice, shipment, G/L entries, VAT entries, customer ledger entries, item ledger entries, value entries, warehouse entries. Click a line to open them.
This is the audit trail. "Where did this G/L entry come from?" is Find Entries on its document number. "What did posting that order create?" is the same. Auditors who know Business Central ask for it by name.