Specific item in a collection

I am trying to use an api to split the url and lookup some data. To lookup what I need I need to get a specific number item returned.

I get this data back

and want to grab the second and third item and put them as their own values.

The third item will sometimes not be included, and I want it to return a null or such so using “Last” won’t work.

I assume I need to use this -

437×882

but I don’t know what I should set for the values. Looking into it this may be for maps or objects?

Any help on how to properly set it up would be appreciated.