Please check my itinerary

Hi! I’m taking my mom (50s) to Singapore next month for a birthday trip. It’s our first out of the country trip together! What do you think about what I planned to do?

FIRST DAY

4pm - Arrival at Changi Airport

5pm - Check in at Hotel Boss

7pm - Dinner (any suggestions?? Preferably near the hotel and affordable)

SECOND DAY

9am - 10:30am - Gardens by the Bay (Cloud Forest + OCBC Skyway/Supertree Observatory)

10:30am - 12nn - Art Science Museum

12nn - 1pm - Lunch at a nearby hawker center

1:30 - 3pm - Marina Bay Sands

4-7pm - River Wonders

Dinner at a near hawker center

THIRD DAY: SENTOSA DAY

Take Sky Cable Car to Sentosa

9am - 12nn - S.E.A. Aquarium

12nn - 1pm - Lunch at Kwee Zeen

1 - 4pm - Trickeye Museum

4:30 - 6pm - Harry Potter: Visions of Magic

Take Sky Cable Car back

Dinner at a near hawker center

LAST DAY

9am - 1:30pm - City Tour

1:30 - 3pm - Lunch (What do you suggest we eat? Fine dining is fine. Just the best restau in SG to celebrate birthday)

4pm - Leave for Changi Airport

5pm - 7pm - Changi Mirror Maze + Canopy Park

11pm - Departure

Thinking of going River Cruise but i don’t know if time will permit (and which day to insert).

Also, how do you suggest we go around? Should we stick to buses/mrt or should I rent a car? Time spent is a factor I consider + Fare fee.

PS: Breakfast is included in our hotel.

EDIT: Would 500SGD be enough for a 4-day trip? It would be for food, fare, and souvenirs. The attraction tickets are not included since I’ll book them earlier.