It’s a beach box.

Have you ever seen a beach box with a second story addition?

To get ideas you can drive around your area and see if you see any houses in your neighborhood where someone has done what you're thinking of and take a picture of it. Also look at pictures on Houzz and save ones you like in an Ideabook. But for a full second story addition you will definitely need to engage the services of an architect. He/she will be able to generate a couple ideas and also solve whatever interior issues you are seeking to solve by doing an addition of this scope.

While you could conceivably get a builder to slap up another story if you give him pictures, you will not get a good result doing that. Builders follow plans and are very literal. If the whole thing isn't completely thought through you will be sorry. Ultimately someone will have to draw up plans in order to get a building permit. For your sanity, make it a professional.

Also be aware that this will be an expensive undertaking and unless the land is very valuable, has sentimental value, or you expect to own this home for the rest of your life, it may not financially be a good idea to do a project of this scope.

We’ve built 3 lovely houses. 😉
Just wondering if anyone here on Houzz had a picture of this style house with an addition.

With a second floor it just stays a vernacular house. Look at detailing of American four squares with full width front porches. Also look at what the regional siding options are- on the north shore of Massachusetts it would be cedar shakes left to weather with off white trim, on a Maine lake it would be the same shingles but dark green or brown trim.

Your cottage reminds me of many of the Church Camp Summer Cottages built in the 19th century. Many, over the years, have had additions. Upwards because they are often compactly built. I’d look at Chautauqua camps for inspiration. I think you could actually do a double front porch, up and down, rectangle on rectangle plan. In any event…have fun with this!

Thank You @Hallet&co , @ptreckel!
I’ll do some research on these styles. Looking forward to working on my little shore project!