It's quite flexible. There is no fixed word order as far as I know. Of course, it would make more sense to use the most common one (subject plus predicate) and, as in other languages, to keep the modifiers close to the parts they modify, but this I believe is a universal rule.
You also might change this most common word order to stress something, putting the stressed part at the beginning. For example:
Magda kupiła czekoladę is a pretty neutral statement informing that Magda bought a chocolate. But if you say
Czekoladę kupiła Magda, you stress the fact that it was the chocolate that was bought by Magda (maybe there are other things that were also bought, but someone else bought them). But this is more advanced stuff I suppose.
What you need to know at this level is that in general, subject followed by a verb is a safe choice.
So your question generally follows the rule, but lacks one verb; it should read:
Muszę wiedzieć, jak* wygląda składnia w języku polskim.
*A tip: "jak" is generally followed by a verb, an adverb or an adjective.
I hope this helps :)