Zapešće je blizu podlaktice.

• zapešće = wrist
• je = is
• blizu = near / close to
• podlaktice = of the forearm / forearm in the form required after blizu

So the structure is literally something like Wrist is near forearm.

Croatian does not use articles like the or a/an.

So:

• zapešće can mean the wrist or a wrist
• podlaktice can mean the forearm depending on context

Croatian usually leaves definiteness to context instead of using articles.

Because blizu normally takes the genitive case.

The basic dictionary form is:

• podlaktica = forearm

But after blizu, it changes to the genitive singular:

• blizu podlaktice = near the forearm

This is a very common thing in Croatian: certain words force the following noun into a specific case.

In normal usage, yes: blizu is followed by the genitive.

Examples:

• blizu kuće = near the house
• blizu škole = near the school
• blizu mora = near the sea

So in your sentence:

• blizu podlaktice is correct because podlaktice is genitive singular.

Je is the 3rd person singular present form of the verb biti (to be).

So:

• ja sam = I am
• ti si = you are
• on/ona/ono je = he/she/it is

Since zapešće is singular, Croatian uses je:

• Zapešće je... = The wrist is...

Zapešće is neuter singular.

A useful clue is that many Croatian neuter nouns end in -e or -o in the nominative singular.

Because it is singular, the verb is still:

• zapešće je = the wrist is

Gender does not change je here, because je is used for all singular genders:

• ruka je = the hand is
• nos je = the nose is
• zapešće je = the wrist is

The base form is podlaktica.

It is a feminine noun, and its nominative singular ends in -a, which is very common for feminine nouns in Croatian.

Its forms here are:

• podlaktica = nominative singular
• podlaktice = genitive singular

So:

• podlaktica = forearm
• blizu podlaktice = near the forearm

Yes, Croatian word order is more flexible than English word order.

The neutral, straightforward version is:

• Zapešće je blizu podlaktice.

But other orders may be possible for emphasis, for example:

• Blizu podlaktice je zapešće.

That can sound more marked or stylistic, depending on context. For a learner, the original order is the safest and most natural choice.

A rough English-friendly approximation is:

za-PESH-chye

A few details:

• z = like English z
• š = sh
• ć = a soft sound somewhat like ty in very quick tube in some accents, or a softer ch
• the cluster šć can be tricky; say it smoothly, almost like sh-chy

You do not need a perfect English equivalent right away. The most important thing is to notice that š and ć are distinct Croatian sounds.

A rough approximation is:

pod-LAK-ti-tseh

More closely:

• po = po
• dlak = dlak
• ti = tee
• ce = tseh

The stress is commonly heard around LAK.

Learners often think of it as meaning near, and that is the most important thing. Grammatically, it behaves like a word that takes the genitive, much like a preposition would.

So for practical learning, it is enough to remember:

• blizu + genitive

Examples:

• blizu grada = near the city
• blizu prozora = near the window
• blizu podlaktice = near the forearm

In standard Croatian, no. In a normal present-tense statement, you should keep je.

Correct:

• Zapešće je blizu podlaktice.

Without je, the sentence sounds incomplete or nonstandard in ordinary usage.

In this context, yes, it most naturally describes physical location: the wrist is near the forearm.

More generally, blizu can also be used in less literal ways, such as:

• blizu kraja = close to the end
• blizu istine = close to the truth

But with body parts like zapešće and podlaktica, the physical meaning is the obvious one.