How would 2 boys say "we need" in spanish?

Firstly, it is important to note that in Spanish the verbs must be conjugated according the subject or the noun in the sentence and must match in number and genre with the noun.

Now, the verb necesitar (to need) is conjugated with the first person in plural nosotros (we) as:

We need

This is because we are talking about two boys (plural subject)