Arrays within structs

Question

the layout of the data in question is: Order ID, Customer ID, List of Product id(separated by comma)
I already have set the order id and customer id.
The issue is that I want to put the list of products in an array, but if I declare the array in the struct, it doesn't exist outside, and I also don't know how to place items in the array

Answer 1

https://code.sololearn.com/c94JJONe9vTa/?ref=app