1. الاستقلال here means that the marriage certificate is the only entry in Record Book Nr. 00, Entry Nr. 00, Page Nr. 00. It exists INDEPENDENTLY of any other entry in that page i.e, there is no other entry concerning anybody in that page.

2. عقب ذلك بما سيذكر كيف يذكر means it is a 100 percent IDENTICAL or TRUE COPY or DUPLICATE COPY of the original as it exists in the court Record Book with not a sigle detail added or removed.

--------------------------------------------------
Note added at 1 day 17 hrs (2021-04-03 12:27:37 GMT)
--------------------------------------------------

‍1. One fundamental thing to bear in mind is that all that jargon is specific to legal documents drafted by كتاب بالعدل, called ''adouls'' in this part of the world. They have a solid sharia background and they usually use a special jargon, phrases and syntactic structures that a modern notary public or the layman would call ''useless verbosity''. They actually don't have to use that type of jargon though they generally tend to. The other thing is that when they do, each is free to pick and choose the terms, phrases and structures they feel like to. Bottomline: most of it pertains to form rather than gist as one of them let me know.
2. The phonetic transcription of the word عقب is /akiba/ or /عakiba/ which means ''after that'' here and could also mean ''upon that'' in other contexts. I am sorry I am not familiar with using the keyboard for tashkeel, so I have opted otherwise.
3. According to the notary public I asked, the word الاستقلال in your text refers to the idea that it is the sole document in that page. Should you not feel comfortable with that, just like myself, you may consider omitting it altogether. More important than that is the notary public says it is a word to word identical copy of the entry which you cannot overlook.
Should you have further enquiries, please don't hesitate to ask.

--------------------------------------------------
Note added at 1 day 20 hrs (2021-04-03 15:40:31 GMT)
--------------------------------------------------

Do you confirm that there is nothing between (اسم المدينة)... و الاستقلال. i.e, that the word الاستقلال comes right after the city name?
What format is the certificate you are sent by the client? Are there no OCR issues in case it is a badly scanned copy?

--------------------------------------------------
Note added at 2 days 3 hrs (2021-04-03 23:08:59 GMT)
--------------------------------------------------

Please note that the suggestion above is exclusive of the phrase ''و الاستقلال عقب ذلك''. Therefore, discard item 3 above.

--------------------------------------------------
Note added at 2 days 8 hrs (2021-04-04 04:11:06 GMT)
--------------------------------------------------

And item 1 in the explanation.