Briefly explain the provisions related to the appeal from orders of National Company Law Tribunal under Section 421 of the Companies Act, 2013.

Section 421 of the Companies Act, 2013 provides the provisions relating to Appeal from Orders of National Company Law Tribunal (Tribunal). It states: Any person aggrieved by an order of the Tribunal may prefer an appeal to the Appellate Tribunal. No appeal shall lie to the Appellate Tribunal from an order made by the Tribunal with the consent of parties. Every appeal under section 421 (1) shall be filed within a period of forty-five days from the date on which a copy of the order of the Tribunal is made available to the person aggrieved and shall be in such form, and accompanied by such fees, as may be prescribed: Provided that the Appellate Tribunal may entertain an appeal after the expiry of the said period of forty-five days from the date aforesaid, but within a further period not exceeding forty-five days, if it is satisfied that the appellant was prevented by sufficient cause from filing the appeal within that period. On the receipt of an appeal under sub-section (1), the Appellate Tribunal shall, after giving the parties to the appeal a reasonable opportunity of being heard, pass such orders thereon as it thinks fit, confirming, modifying or setting aside the order appealed against. The Appellate Tribunal shall send a copy of every order made by it to the Tribunal and the parties to appeal.