Suna bauta wa Allah kullum.

Because su is only the pronoun they.
To make a present/imperfective clause, Hausa adds the imperfective marker na. So:

• su = they
• su + na = suna

In standard writing, this is usually written as one word: suna.

Because bauta normally takes its object with the preposition wa. So Hausa says:

• bauta wa Allah = worship God

A learner should treat bauta wa as a set pattern. It is not natural here to say bauta Allah.

In practical learning terms, yes—you can treat bauta wa as the verb phrase to worship / to serve.

More technically, Hausa often uses forms like this in ways that are closely related to verbal nouns, but for a learner the important point is simple: in suna bauta wa Allah, bauta wa is the action part of the sentence.

It can potentially do either, depending on context, because suna is an imperfective form. But with kullum in the sentence, the natural reading is habitual:

• they worship God regularly
• they worship God every day
• they always worship God

So here it is not mainly about one moment right now.

Kullum often means every day, always, or continually, depending on context.

In this sentence, it gives the idea of regular repetition. So English translations like these can all fit:

• every day
• always
• continually

That is a very natural place for an adverb of time in Hausa. The basic flow here is:

suna + bauta wa Allah + kullum

So the sentence ends with the time expression.

You can also move kullum to the front for emphasis:

• Kullum suna bauta wa Allah.

But the original order is completely normal.

Yes. Bauta wa can carry the idea of serving, being devoted to, or worshipping, depending on context.

With Allah, the religious sense worship God is the most natural translation. But the wider idea of devoted service is still there.

You can say:

Ba sa bauta wa Allah kullum.

That means They do not worship God every day / always.

Notice the change:

• affirmative: suna
• negative: ba sa

This is a very common Hausa pattern in the imperfective.

You just change the subject form:

• Ina bauta wa Allah kullum. = I worship God every day.
• Kana bauta wa Allah kullum. = You (masc. sg.) worship God every day.
• Kina bauta wa Allah kullum. = You (fem. sg.) worship God every day.
• Yana bauta wa Allah kullum. = He worships God every day.
• Tana bauta wa Allah kullum. = She worships God every day.
• Muna bauta wa Allah kullum. = We worship God every day.
• Kuna bauta wa Allah kullum. = You (plural) worship God every day.
• Suna bauta wa Allah kullum. = They worship God every day.

No. Allah is a proper name, so it stands on its own. Hausa does not use an article like English the in this kind of sentence.

So wa Allah is exactly what you want here.

A rough English-friendly guide is:

SOO-nah BOW-tah wah ah-LAH kool-loom

A few helpful points:

• su sounds like soo
• au in bauta sounds like ow in cow
• wa is like wah
• u in kullum is like oo
• Hausa vowels are usually kept clear and pure, not reduced as much as in English

So try to say each vowel clearly rather than swallowing unstressed syllables.