I believe so. Since what forks can do can also be done with a pair of chopsticks.
Need to grab a piece of baby carrot: chopsticks
A piece of grilled meat (most of the time the food are pre-cut prior to serving): chopsticks
I don't see anything besides steaks that needs to be eaten with forks, and they're not very common in everyday meals in VN.
However in “quán ăn bình dân” small eateries, or the Vietnamese equivalent to dinners. People usually eats with spoon and forks, since foods are often served together with rice on a single plate, meaning it's harder to eat the rice (and not the entrées) using chopsticks this way.
Btw rice at home are serve in hand-held bowls, which assisted greatly in using just chopsticks.
Note that the bowl is usually held by hand while eating