Wij geven morgen een presentatie op school.

Literally, geven means to give, but in this context it means to deliver or to present—just like English to give a presentation. So

• Wij geven morgen een presentatie → “We will deliver/present a presentation tomorrow.”

Dutch has a common main‐clause word order:

1. Subject (Wij)
2. Finite verb (geven)
3. Time (morgen)
4. Object (een presentatie)
5. Place (op school)

So Wij geven morgen een presentatie op school follows S-V-T-O-P.
You can shift morgen to the very front for emphasis:

• Morgen geven wij een presentatie op school (Tomorrow we will give a presentation at school).

The choice of preposition changes the meaning:

• op school = at school (location of an event)
• naar school = to school (movement toward)
• in de school = inside the school building (with the definite article)

Because we’re talking about where the presentation takes place, we use op school.

Dutch often omits the article with institutions or locations in set expressions:

• op school (at school)
• op kantoor (at the office)
• in de school would imply “inside the specific school building.”

Here, op school simply means “at school” in general.

• een = a/an (introducing something not previously specified)
• de = the (referring to a specific, known presentation)

So if you’re mentioning the presentation for the first time:

• Wij geven morgen een presentatie… (“…a presentation.”)

If both speaker and listener already know which one:

• Wij geven morgen de presentatie… (“…the presentation we discussed.”)

Yes.

• wij is the full, emphatic pronoun (“we”).
• we is the weak or reduced form, more common in spoken or informal Dutch.

Both mean the same thing; we just sounds more casual.

Dutch frequently uses the present tense for near‐future actions, especially if a time adverbial is present.

• Wij geven morgen… can be understood as “We will give tomorrow…”

If you want to be explicit, you can use gaan:

• Wij gaan morgen een presentatie geven op school (“We are going to give a presentation tomorrow at school.”)