と and や can be used to list things with the difference being that と indicates an exhaustive list, while や means that there can be more in the list, than what’s mentioned.
I know that と can also mean ‘with’ in cases like
e.g.: “公園になおさんと行きました” = “I went to the park with Nao”.
Coul I replace the と with a や to say that I went there with Nao and some more?
“公園になおさんや行きました” = “I went to the park with Nao (and someone else).”?