Learn Spanish (Latin America): Estudio mucho antes del examen.

In Spanish, the verb ending usually tells you who is doing the action. Estudio ends in -o, which means "I study." You can include yo for emphasis, but it is completely normal to leave it out.

Why does the sentence use mucho instead of mucha or muchos?

Here, mucho is acting as an adverb (a word that describes an action). It is telling us how much you study. When mucho describes a verb rather than a noun, it always stays in its default masculine singular form and never changes its ending.

Why does it say del examen instead of de el examen?

In Spanish, whenever the preposition de (which means of or from) is immediately followed by the masculine word for "the" (el), they must combine to form the contraction del. You will never see de el written together as two separate words.

Why do we need the de in antes del? Doesn't antes already mean "before"?

When you want to say "before a specific thing or event," you must use the phrase antes de. In this sentence, it is "before the exam." If you just use antes by itself without a noun after it, it means "beforehand" or "earlier."