Părintele citește mesajul.

Romanian usually puts the definite article at the end of the noun, not before it as English does.

So:

părinte = parent / priest / father
părintele = the parent / the priest

mesaj = message
mesajul = the message

This is one of the most noticeable differences between English and Romanian. Instead of a separate word like the, Romanian often uses an ending attached to the noun.

The definite article changes depending on the noun’s form and gender.

In this sentence:

părinte ends in -e, so the definite form is părintele.
mesaj ends in a consonant, so the definite form is mesajul.

So the ending is not always the same. Romanian has several definite article forms, and learners gradually get used to which nouns take which ending.

It can mean either, depending on context.

The noun părinte can mean:

parent
or
father/priest in a religious sense

So părintele citește mesajul could mean the parent reads the message or the priest reads the message. On its own, the sentence is ambiguous. Usually the wider context makes the meaning clear.

Citește comes from the verb a citi, meaning to read.

Here, citește is the 3rd person singular present tense form, used for:

he reads
she reads
it reads

Because the subject is părintele, the verb must be singular: citește.

A few present-tense forms of a citi are:

eu citesc = I read
tu citești = you read
el/ea citește = he/she reads
noi citim = we read
voi citiți = you all read
ei/ele citesc = they read

It can mean reads or is reading, depending on context.

Romanian present tense often covers both:

he/she reads
and
he/she is reading

So părintele citește mesajul could mean either:

The parent reads the message
or
The parent is reading the message

If the situation is happening right now, Romanian often still just uses the normal present tense.

In this sentence, you know mostly from word order and meaning.

Părintele citește mesajul follows the normal Romanian pattern:

subject + verb + object

So:

părintele = the one doing the action
citește = the action
mesajul = the thing being read

Also, semantically, a message does not normally perform the action of reading, so mesajul is naturally understood as the object.

Unlike some other Romanian sentences, there is no special object marker here, because mesajul is inanimate. With certain animate direct objects, Romanian often uses pe, but not here.

The most neutral and natural order here is:

Părintele citește mesajul.

Romanian word order is somewhat flexible, but subject + verb + object is the basic pattern.

Different orders are possible in some contexts for emphasis, but they usually sound more marked, less neutral, or require other changes. So for a learner, this sentence is a very good standard model.

Romanian often leaves out subject pronouns when they are not needed.

The verb form already tells you the person and number, and the noun subject is explicitly stated here anyway:

părintele citește mesajul

Because părintele is already the subject, there is no need to add el or ea.

In fact, Romanian often sounds more natural without an extra pronoun unless you want emphasis or contrast.

They are important Romanian sounds:

ă is a short, neutral vowel, somewhat like the a in sofa.
ș is pronounced like English sh.

So:

Părintele is approximately puh-RIN-te-le
citește is approximately chee-TESH-te
mesajul is approximately meh-SAH-zhul

A few helpful notes:

ci in citește sounds like chee
șt sounds like sht
j in mesajul sounds like the s in measure

Mesaj is a neuter noun in Romanian.

Romanian neuter nouns behave like:

masculine in the singular
and
feminine in the plural

In this sentence, it is singular, so it behaves like a masculine noun, which is why the definite form is mesajul.

This matters more when you later learn adjectives and plural forms, but even here it helps explain why the noun looks the way it does.