Boonop is die plan gereed.

Boonop means moreover, besides, in addition, or on top of that.

So Boonop is die plan gereed means something like:

• Moreover, the plan is ready.
• On top of that, the plan is ready.

It is a linking adverb that adds another point to what was said before.

Afrikaans often uses verb-second word order in main clauses. That means the finite verb usually comes in the second position.

So when the sentence starts with Boonop, that counts as the first element, and the verb is moves into second position:

• Boonop is die plan gereed.

Compare:

• Die plan is gereed. = The plan is ready.
• Boonop is die plan gereed. = Moreover, the plan is ready.

This is very normal in Afrikaans and one of the first word-order patterns learners notice.

Yes, you can, but the emphasis changes slightly.

• Boonop is die plan gereed.
  This foregrounds boonop and sounds like Moreover, the plan is ready.

• Die plan is boonop gereed.
  This keeps the plan as the starting point and means something like The plan is, moreover, ready or The plan is also ready.

Both are grammatical, but the original sentence sounds a bit more like written or structured discourse, where you are adding a new point.

Gereed usually means ready.

Depending on context, it can also suggest:

• prepared
• finished
• set
• completed and ready for use

In die plan is gereed, the most natural meaning is the plan is ready or the plan is finished/prepared.

Yes. In this sentence, gereed is an adjective used predicatively, meaning it comes after is:

• Die plan is gereed.

That is similar to English:

• The plan is ready.

You would not normally translate it here as an adverb.

Yes. Afrikaans uses die as the definite article for the in all genders and numbers.

Unlike languages such as German or Dutch, Afrikaans does not change the definite article for masculine, feminine, neuter, or plural in this basic way.

So:

• die plan = the plan
• die man = the man
• die vrou = the woman
• die kinders = the children

That makes articles simpler than in many other Germanic languages.

In Afrikaans, is is used much more widely than English is. In the present tense of to be, Afrikaans uses is for all persons and numbers:

• Ek is = I am
• Jy is = you are
• Hy/Sy is = he/she is
• Ons is = we are
• Julle is = you all are
• Hulle is = they are

So Afrikaans does not have forms like am/are/is. It just uses is.

Yes, but it sounds a little more formal or polished than some simpler alternatives.

It is common in writing and in more careful speech. Depending on context, speakers might also use things like:

• ook = also
• verder = furthermore
• daarby = besides / in addition

But boonop is completely natural and useful to know.

A rough English-friendly guide would be:

• Boonop ≈ BOAR-nop or BOH-nop
• is ≈ iss
• die ≈ dee
• plan ≈ plahn
• gereed ≈ khuh-REET or guh-REET depending on accent

A rough full pronunciation:

• BOH-nop iss dee plahn khuh-REET

A few notes:

• die in Afrikaans is usually pronounced like dee, not like English die.
• The g in gereed is usually a guttural Afrikaans/Dutch-type sound, which may be difficult for English speakers.

In normal Afrikaans spelling, you usually do not need a comma just because a sentence begins with an adverb like boonop.

So the standard form is:

• Boonop is die plan gereed.

A comma would only appear if the structure were different or if the writer wanted a marked pause for stylistic reasons.

Yes. Plan is a very close cognate of the English word plan and often means the same thing.

It can refer to:

• an idea or proposal
• a strategy
• a schedule or intended course of action

So die plan is straightforwardly the plan in most contexts.

No. Afrikaans does not capitalize all nouns.

So in this sentence:

• plan is lowercase
• gereed is lowercase

Only the first word of the sentence is capitalized here:

• Boonop is die plan gereed.

That is much closer to English than to German.

Grammatically, Afrikaans adjectives can often appear before nouns, but with gereed, that would usually sound unnatural in this context.

The normal, natural structure is:

• die plan is gereed = the plan is ready

Using gereed before the noun would not usually be the best choice for this meaning. So learners should strongly prefer the predicate pattern:

• noun + is + gereed