Hi @Ramtin, in my company, as @ScottShearer suggested, we save back to the item in the document library the approve/reject decision, the name of the approver, the date of the approval and any comments made in the approval email. That way we have an audit trail of the approval specific to each document. If more than one approver is needed then we use parallel branching and in the document library have the same columns as above but named differently, e.g. Approver2, ApproveDate2 etc.
In the example below we also automatically add a next review date for 6 months ahead and a separate flow runs every day to check which documents needs reviewing and to send it to the approvers.
Come back with further questions about any of this.

Rob
Los Gallardos
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