The following code fixes the syntax.
In order to fix the logic flaws (if any) you should tell us what your program is expected to do.
#include<stdio.h>
void RevArr(int arr[], int size);
void Rev(int arr[], int size);
int main()
{
int size;
printf("Enter the size of array :");
scanf("%d", &size);
int arr[size];
for(int i=0;i<size;i++)
{
printf("Enter element \n");
scanf_s("%d", &arr[i]);
}
Rev(arr, size);
return 0;
}
void RevArr(int arr[], int size)
{
}
void Rev(int arr[], int size)
{
for(int i=0;i<size;i++)
{
printf("%d ", arr[i]);
}
}