What does se mean in front of a word?
That cannot be answered in a few short sentences. I would search for previous threads on the use of the reflexive pronoun se. Among the pronominal usages are reflexive se, passive se, reciprocal se, impersonal se, de-transitizing se, se with unforseen circumstances, se to emphasize completion or entirety and probably many others that I can't think of at the moment.
What does se mean in front of a word? For Ex. se necesita, se baila, se va, se compra, se tiene, y se toma.
If you are expecting a short answer, then it is NOTHING. It does not mean anything in particular, and it cannot be translated into English, because you don't have something like it. Besides, they can be used in many ways with different meanings, so if you don't put them in sentence and in a context, we can't even tell you what they mean at all.
So, what is it for and how do I learn it? It will take you time to learn how to use them and why, or a long time if you follow the wrong method or textbook.
1) get a good book and learn one use at a time.
2) if the book calls everything with a "se" reflexive, throw the book away and get a decent one.
Lots of possible meanings/functions, depending on the context. For a detailed discussion uses of 'se'.
Hey, it means it is a reflexive verb. for example : se baila : bailarse
"Se baila mucho en mi pueblo"
It means, people dans a lot in my town., but you don't use a subject, so there is no one spesific who does it. It's a little bit like "passive" but it's not exactly passive.