Learn Dutch: Ik lees altijd enkele recensies over het artikel. - I always read a few reviews about the item.

We add an -n to these quantifying words only when they refer to people AND stand on their own without a noun. Here, enkele is followed right away by the noun it describes (recensies), so it acts as an adjective and gets the standard -e ending, but no -n.

Could I use een paar instead of enkele in this sentence?

Yes, you could say een paar recensies. Both translate to a few reviews. Enkele is a slightly more formal or written-style way to say a few or some, whereas een paar is very common in everyday spoken Dutch.

The translation says the item, but doesn't het artikel mean the article?

It can mean both! Het artikel can refer to a written text in a newspaper, but it is also commonly used in stores or webshops to refer to a product or an item. Because this sentence mentions reading reviews (recensies), the person is clearly looking at a product to buy.

Why does altijd come immediately after the verb lees?

In a standard Dutch main clause that starts with the subject (Ik), the verb (lees) takes the second position. Adverbs of time, like altijd, generally belong very early in the sentence and will usually come right after that verb.