What do you wear on a cruise in Alaska?

I am 14 years old and I am having a hard time finding a dress that isn’t a tube top and is not too revealing.
Also, what type of clothes should I pack for the day? Do I pack shorts or jeans/ long pants? Everyone keeps telling me something different.
My biggest concern is a dress though, I don’t want it too be too expensive since I’ll only wear it 1 or 2 times. If anyone has any good websites I should check out then please post them.
Thank you

alaska luxury fishing vacation