Rob takes 2 pairs of shoes (sneakers and sandals) and 3 pairs of shorts (red, blue, and white) when he goes on a trip list all the possible outfits with 1 pair of shoes and 1 pair of shorts that rob could wear

To find the answer you multiply 2 with 3 to find the total number of combinations.
2 X 3 = 6
So there are 6 combinations.

However, the question asks for a list of all the combinations.
So we simply list them.

                 --- Red shorts
Sneakers --- Blue shorts
                 --- White shorts

              --- Red shorts
Sandals --- Blue shorts
              --- White shorts

Sneakers and red shorts.
Sneakers and blue shorts.
Sneakers and white shorts.
Sandals and red shorts.
Sandals and blue shorts.
Sandals and white shorts.

So there is your list. :)