Der Glückwunsch kommt von uns.

Glückwunsch is a masculine noun, so its basic article is der.

• der Glückwunsch = nominative singular
• den Glückwunsch = accusative singular
• dem Glückwunsch = dative singular
• des Glückwunsches / Glückwunschs = genitive singular

In this sentence, der Glückwunsch is the subject, so it appears in the nominative.

Because all nouns are capitalized in German.

So:

• der Glückwunsch
• das Haus
• die Stadt

This is one of the most noticeable spelling differences from English.

Almost, but not always in exactly the same way.

Glückwunsch is a singular noun meaning something like:

• congratulation
• congratulatory message
• expression of congratulations

English often prefers the plural congratulations, but German can use the singular noun der Glückwunsch.

Related forms:

• Herzlichen Glückwunsch! = Congratulations!
• die Glückwünsche = congratulations / best wishes (plural)

So in this sentence, der Glückwunsch can sound like the congratulatory message or the congratulations.

Because German main clauses usually follow the verb-second rule.

In Der Glückwunsch kommt von uns:

1. Der Glückwunsch = first element
2. kommt = second element
3. von uns = the rest

That is standard German word order.

You could also change the emphasis:

• Von uns kommt der Glückwunsch.

This is still grammatical, but now von uns is the first element, and kommt still stays in second position.

Von usually means from or of, depending on context.

Here, von uns means from us.

So kommt von uns literally means comes from us. In natural English, that often means:

• is from us
• comes from us
• is being sent by us

This is a normal way in German to show the source or sender of something like a greeting, message, gift, or card.

Because von always takes the dative case, and the dative form of wir is uns.

Personal pronouns:

• nominative: ich, du, er, wir
• dative: mir, dir, ihm, uns

So:

• wir = we as the subject
• uns = us after a dative preposition like von

That is why von uns is correct, not von wir.

Yes, you can, and it would be understood.

The difference is mainly one of nuance:

• Der Glückwunsch kommt von uns. = the congratulation/message comes from us, with a slight sense of origin or delivery
• Der Glückwunsch ist von uns. = the congratulation/message is from us, a bit more direct and static

Both are possible, but kommt von uns can sound especially natural when talking about greetings, messages, letters, cards, or gifts.

Yes, Glückwunsch is singular here.

Plural:

• der Glückwunsch = singular
• die Glückwünsche = plural

So:

• Der Glückwunsch kommt von uns. = The congratulation/message comes from us.
• Die Glückwünsche kommen von uns. = The congratulations come from us.

English often uses plural congratulations, while German may use either singular or plural depending on the situation.

A rough pronunciation guide is:

GLÜK-voonsh

A few important points:

• ü is a front rounded vowel that English does not really have
• ck is a hard k sound
• w in German sounds like English v
• sch sounds like English sh

So Glückwunsch sounds approximately like glyuk-vunsh, though that is only an approximation.

Because the subject is der Glückwunsch, which is third person singular.

The verb kommen is conjugated like this in the present tense:

• ich komme
• du kommst
• er/sie/es kommt
• wir kommen
• ihr kommt
• sie/Sie kommen

Since der Glückwunsch is like er grammatically, the correct form is kommt.

Yes. German allows some flexibility, as long as the finite verb stays in second position in a main clause.

For example:

• Der Glückwunsch kommt von uns.
  Neutral order.
• Von uns kommt der Glückwunsch.
  Emphasizes from us.

Both are grammatical, but the first version is the most neutral and straightforward for learners.

It is neutral. Nothing in it is especially formal or especially informal.

• uns simply means us
• there is no formal Sie form here
• the wording could fit everyday speech, a card, or a written message

So it works in many contexts without sounding strange.