Let me start by saying that I live 10 miles from Portland.
Is there any possibility that you will be in Portland on the first Friday in September, which this year will be the 1st? if so, you can enjoy the First Friday Art Walk. The Portland Museum of Art is free for the evening, all of the galleries in the Arts District around it are open, people are selling things they make on the street, the galleries are often serving wine and cheese and people are roaming Congress Street from gallery to gallery with cups, there can be flash mobs, theater, top notch musicians of various kinds playing at various venues for free, and so forth.
In my experience, the restaurants in Freeport are for eating when you’re out shopping and hungry, not destinations. The lobster pound in South Freeport village, Harraseeket Lunch and Lobster, would be my choice there, because it’s a real down home lobster place.
BUT if you want lobster or your standard fried seafood with a spectacular view, The Lobster Shack at Two Lights in Cape Elizabeth is BY FAR your best choice. In fact, there is simply no comparison. (The blueberry tarts are good, too.) And after lunch you can climb around on the incredible rocky promontory sticking out into the sea and investigate tidal pools as the waves crash just beneath you.
I’m fond of Gilbert’s Chowder House’s seafood chowder. They USED to have fantastic clam cakes. but alas, now they are the usual blah pre-made product. Don’t order them. It’s a nice place to have lunch, especially if the weather’s nice and you can sit on the deck out back. It’s not a spectacular view or anything, but it’s nice. And they have a nice selection of local draft beers.
Fore Street is reputed to be the best restaurant in Portland. I’ve never been there. Not yet, anyway.
I understand that you have to get reservations well in advance. My personal favorite, Bresca, which was a 14-seat place, alas has closed. Duck Fat is great for things like a cornet of fries cooked in duck fat, with duck gravy and cheese curds. Be still my heart.
I’ve eaten and Street&Co, and it was pretty good, but no where near as good as Bresca and didn’t rock my world.
Breakfast: Becky’s Diner. Have the homemade corned beef hash. Another choice, the Miss Portland Diner.
Breakfast in Bar Harbor, Jordan’s Pancake House.