بالنسبة للشهادة، دي معتمدة.

Here بالنسبة means regarding, as for, or with respect to.

In this sentence, بالنسبة للشهادة is setting the topic:

• As for the certificate...
• Regarding the certificate...

It is a very common way to introduce a topic in both formal and everyday Arabic.

Because بالنسبة is normally followed by لـ.

So the full idea is:

• بالنسبة لـ الشهادة

But in actual writing, that لـ attaches to the following word, giving:

• بالنسبة للشهادة

In pronunciation, the ش is pronounced strongly, so you hear something like ... lish-shahāda.

Because شهادة is a feminine noun, and دي is the Egyptian Arabic feminine singular demonstrative, meaning this.

So:

• ده = masculine singular this
• دي = feminine singular this

Since شهادة is feminine, دي is the correct form.

Because it agrees with شهادة.

Arabic adjectives and participle-based descriptors usually agree with the noun in gender and number. Since شهادة is feminine, the word becomes:

• معتمدة = feminine
• معتمد = masculine

So دي معتمدة matches the feminine noun being talked about.

That is very normal in Egyptian Arabic.

Literally, دي means this, but in sentences like this it often works naturally where English would say it. So:

• دي معتمدة literally: this is accredited naturally: it is accredited

This is a common Arabic pattern, especially in speech.

Arabic usually leaves out is/are in present-tense sentences like this.

So:

• دي معتمدة literally: this accredited meaning: this is accredited / it is accredited

This is called a nominal sentence. The present-tense is is understood and does not need to be said.

Because it has a topic-comment structure:

• بالنسبة للشهادة = the topic
• دي معتمدة = the comment about that topic

So the sentence works like:

• As for the certificate, it is accredited.

This kind of structure is very natural in Arabic, especially when clarifying or responding to a question about one specific thing.

Yes, absolutely.

• الشهادة دي معتمدة = This certificate is accredited
• بالنسبة للشهادة، دي معتمدة = As for the certificate, it is accredited

The version with بالنسبة feels more like you are introducing or isolating the topic. It is especially useful if someone asked about several things and now you are answering specifically about the certificate.

It is mostly neutral Arabic with one clearly Egyptian colloquial feature: دي.

• بالنسبة is common in both Standard Arabic and colloquial Arabic.
• معتمدة is also common in both.
• دي is colloquial Egyptian.

A more Standard Arabic version might be:

• بالنسبة للشهادة، فهي معتمدة or
• هذه الشهادة معتمدة

So the sentence you have is very natural for Egyptian speech or informal writing.

Not exactly. It is a participle used like an adjective.

It comes from the verb related to approving / accrediting, but here it describes the certificate's status:

• accredited
• recognized
• approved

So in this sentence, معتمدة is functioning more like an adjective than like a full verb.

A rough pronunciation would be:

bennisba lish-shahāda, di moʿtamda

A few helpful notes:

• بالنسبة is often said roughly like bennisba
• للشهادة is pronounced with a strong sh
• معتمدة in Egyptian speech is often moʿtamda

You do not need to pronounce it exactly like the spelling looks in English letters, but that approximation is a good start.