Your wife does not need to follow any strategy "to get Money and Divorce" since the Family Court has already passed an order in her favour. Now, in the High Court, the Burden of Proof is on you to prove that the order granting for Divorce and Maintenance needs to be set aside.
If the High Court allows your 'Stay' application, then you won't need to pay the Maintenance until the 'Stay' subsists. Your appeal might be allowed if the Family Court faulted in applying the correct law or did not appreciate all the facts of your case, otherwise it might get dismissed. The High Court may even pass an order altering the Maintenance Amount.
The appeal proceedings in the High Court involve written as well as oral submissions. You will need to appear if the Court wants you to, but it is generally not required in the appeal cases.
An appeal starts with the filing of a Memorandum of Appeal, containing the objections to the orginal decree. Then, the notice is issed to the other party and is allowed time for filing counter-objections. In your case, there will be consideration on the Stay Application also. So, the other party will file reply on that too. After this, there will be oral arguments and then the High Court will decide on whether to allow or dismiss your appeal.