Hello everyone! First post here (I posted a similar question on Reddit but I thought this forum would fit better).

I'm thinking about visiting the USA for the first time in the summer of 2022 or 2023. I will travel with my brother and my mother, who is not very old but tends to get tired easily. I haven't laid out a full plan yet, I'm just wondering about whether the ideas I have floated around so far are feasible.

We'd like to visit New York and then go to Chicago to meet some friends who live there.
I plan on doing something like this:

- Fly to NY and spend 3 full days there (this means 4 or 5 days including jet lag adjustment, transfer from the airport and car rental upon leaving)

- Road trip: 2 or 3 days. I thought about seeing Niagara Falls but I'm not sure about timing and visas required to cross the Canadian border. Is there anything else worth seeing along the way? I guess you'd need to get to Niagara Falls during the day to enjoy it fully, so we'd better allot 3 days for the trip, but I feel like one day is going to be wasted if we cannot really see anything else.

- Chicago: 3 days including arrival (ideally, arriving before noon on the first day and immediately giving back the rental car since we would use public transport). Then we'd fly back home from Chicago.

Do you think this is feasible? What would you suggest to see along the way? Would a normal sedan be enough for 3 people and luggage? Thank you in advance~