Ik ben wat moe, dus ik ga nu slapen.

Here, wat does not mean what. In this sentence, it means somewhat, a bit, or kind of.

So ik ben wat moe is a natural, everyday way to say that someone is a little tired. It sounds a bit softer than a stronger phrase like ik ben erg moe.

Because moe is an adjective used after zijn.

Dutch often uses the pattern:

subject + zijn + adjective

So:

ik ben moe = I am tired
hij is blij = he is happy

When an adjective comes after zijn like this, it normally stays in its basic form.

Because dus is linking two complete main clauses:

Ik ben wat moe
ik ga nu slapen

In standard Dutch writing, it is normal to put a comma before dus when it connects two full clauses.

In this sentence, dus works like a connector between two main clauses, so the second clause keeps normal main-clause word order:

ik ga nu slapen

That is why you get:

Ik ben wat moe, dus ik ga nu slapen.

A useful comparison is daarom:

Ik ben wat moe. Daarom ga ik nu slapen.

With daarom, the verb comes before the subject because daarom takes the first position in the clause. With dus in this kind of sentence, you usually keep ik ga.

Because ik ga nu slapen means something like I’m going to sleep now or I’m going to bed now. It expresses an intention or an action that is about to happen.

By contrast, ik slaap nu means I am sleeping now, which would sound odd if you are saying it out loud while still awake.

So in real life, ik ga nu slapen is the natural choice.

Because after gaan used in this way, Dutch normally uses a bare infinitive, without te.

So you say:

ik ga slapen
not ik ga te slapen

This is similar to other verb combinations in Dutch where one verb is followed directly by another infinitive.

Because in a Dutch main clause with more than one verb, the conjugated verb usually comes in second position, and the other verb goes later in the clause.

Here:

• ga is the conjugated verb
• slapen is the infinitive

So the structure is:

ik + ga + nu + slapen

That is a very normal Dutch word order.

Yes. Nu can move, depending on emphasis.

These are all possible:

Ik ga nu slapen.
This is the most neutral version.

Nu ga ik slapen.
This puts extra emphasis on now.

The first one is probably the most natural if you are just stating the fact.

Not exactly.

gaan slapen focuses on going to sleep.
naar bed gaan focuses on going to bed.

You can naar bed gaan without actually sleeping yet, for example if you want to read first. So ik ga nu slapen sounds a bit more direct: the speaker intends to sleep now.

Yes, absolutely.

Ik ben een beetje moe is perfectly natural and very clear.
Ik ben wat moe is also natural, but a little shorter and often a bit more conversational.

Both are good Dutch. The difference is mostly style and tone, not basic meaning.

moe is pronounced roughly like moo in English.

The oe spelling in Dutch usually sounds like the oo in food.

The g in ga is usually a throat sound in standard Netherlandic Dutch, not the English g in go. In some southern accents, especially in Belgium and the south of the Netherlands, it can sound softer.

So for many learners, moe is easy, but g takes a bit of practice.