In terms of the law, an appeal is basically a process under which cases are been reviewed and a party request to do changes in a decision which are been officially made. It functions in two ways as in the process of error correction and process of clarifying and differentiate law.
In the end of any cases in a lower court, the party who loses the case has full right to review that particular case in higher court
in a hope that decision may get changed. In such particular case, an appeal is made to the higher courts.
An appeal is not a rehearing of your cases neither it’s a new trial of your case. One can’t represent new evidence or any new witness in front of a new judge. These things are only possible in exceptional circumstances.
'Hope it was informative'