Im will b in HCM on these date.
My question is do we need to get a visa to enter vietnam or there is VOA. Where is the best place to stay. Im looking for budget hotel and what are the must see place in HCM
There is no VOA at land borders, so if you are crossing by land you will need to get a visa before hand.
If arriving by air there is VOA but it isn't simply issued on arrival you need to do some paper work first, (there are several threads to this on the Visa forum).
According to your dates you are only in HCM for a few days, not sure if you can see much in that time?!