I see....
1) Hoan Kiem Lake and Hoan Kiem Area (AKA old Quarters)
Best to visit there over the weekends because the Police will block ALL THE ROADS and it becomes a HUGE WALKING AREA
- - Within this area, you can walk around the lake which is already very popular with the locals for things like jogging, strolling their dogs, Pat-tor
- - Vietnam Egg coffee (Try both hot and iced)
- - Vietnam Sticky rice
- - Bun Bo Nam Bo
- - Hoan Kiem Weekend Night Market (The Biggest in Vietnam iirc)
- - Famous Trang Tien ice cream
- - Hanoi Opera House
- - Beer Street
2) West Lake aka Ho Tay
3) Pottery Village (Need to travel outside of Hanoi city around 45-mins to 1 hour)
4) Lotte Building Observation Deck
5) St Joseph Cathedral
6) Ho Chi Minh Mausoleum
7) Hanoi Train street
Outside of Hanoi....
You can consider 2D1N stay Ha Long Bay
and 3D2N stay SAPA Mountains but do consider that the travel up to SAPA is around 6 to 8 hours by Car or bus or train