Learn Dutch: Ik houd niet van vlees.

In Dutch, niet usually comes after the main conjugated verb, which is houd here. Additionally, when a sentence has a prepositional phrase (a phrase starting with words like of, for, in, at), niet is placed directly before it. Therefore, it goes right before van vlees.

Since vlees (meat) is a noun, why don't we use geen for negation?

Normally, you use geen to negate an indefinite noun (for example, Ik eet geen vlees means 'I eat no meat'). However, in this sentence, you are negating the verb phrase houden van (to like). Because the noun is attached to the preposition van, we must use niet.

Why do we need the word van in this sentence?

By itself, the Dutch verb houden just means 'to hold' or 'to keep'. If you want to say that you like or love something, you always have to use the fixed combination houden van.

Does houden van mean 'to like' or 'to love'?

It can mean both! When you are talking about people, houden van usually means 'to love'. But when you are talking about food, activities, or things, like vlees, it is the standard way to say you 'like' or 'really like' them.