Questions & Answers about Ми їдемо на північ.
Ми means we.
You do not always have to include it, because the verb ending -емо in їдемо already shows we. So:
- Ми їдемо на північ.
- Їдемо на північ.
Both can work.
Including ми can make the subject clearer or slightly more emphatic.
Because їхати / їздити is used for going by some kind of transport, while йти / ходити is used for going on foot.
So:
- Ми їдемо на північ. = We are going north by vehicle / transport
- Ми йдемо на північ. = We are going north on foot
English go does not always show this difference, but Ukrainian usually does.