For Glacier National Park, is it worth going, if only sticking with overlooks and short easy hikes? (less than a mile roundtrip, flat hikes) Or are most of the more scenic areas only accessible by harder longer hikes?
If you think it's worth going to, can you please recommend short easy flat hikes to waterfalls or lakes in the park?
Thanks

Absolutely worth it, although there are not many places less than a mile out and back other than viewpoints. We went a couple years ago and spent six days and nights split between west and east (which we liked better). I had a bad knee and one in our group was over 80 and not able to do some of the longer hikes.

You can however take the boat trips (we did them on three of the four lakes) and there are many scenic points on the Going to the Sun Road. Our group didn't do many longer hikes other than around Swiftcurrent Lake, which the 80+ year old skipped and waited at the lodge. However, she did power through the Grinnell Lake (NOT the glacier!) hike. She said it was a bit harder than she thought it would be (the walk between the two boats does climb a small hill), but she rested part way and was happy to make it. The lake shore at Swiftcurrent has a trail and even if you don't go the whole way, is scenic and almost flat. I can't recall others that were fully flat. The park service (even these days) usually has lists of easier walks. Look for accessible activities.

It sure is. .It's one of the premiere national parks like Yosemite and Yellowstone.

Just go and you will not regret it. There are a number of easy hikes in the park and the visitor centers are beautifully situated. Going to the sun road is a very beautiful drive. Big horn sheep is easily seen in the park. Many Glacier hotel is beautiful, and also the Lake McDonald lodge.

Ask a park ranger at the visitors center which hikes would be appropriate for you. They will be happy to help and will give you a map of where they are located.

Do any of you know which are the scenic flat easy hikes under one mile round trip where you can see waterfalls or a lake?

alltrails.com lists every trail with length, terrain and photos. There are such trails as you are looking for, but I have not been on them.

I do urge you to take the boat ride on Two Medicine Lake. It is spectacular. You might need tickets in advance....

If you go to the GNP website, you will find some of the suggested easy family hike.

St Mary falls will fit your needs. The boat tours are really good if you want to experience the lakes. Logan pass visitor center has easy walks, and the visitor center will give you a lot of information.

Take a look at the "Family-Friendly Hiking" at Glacier National Park https://www.nps.gov/glac