What are you having trouble with? I have good sources for my Arabic classes and I'll translate what it means to you.
Apparently, this is what you need to focus on, my comments will be in bold:
Students are assessed on their ability to communicate effectively through writing in Arabic.
Students need to:
● communicate effectively in writing for a variety of purposes across a range of specified
contexts
● write short texts, using simple sentences and familiar language accurately to convey
meaning and exchange information
● produce clear and coherent text of extended length to present facts and express ideas and
opinions appropriately for different purposes and in different settings
● make accurate use of a variety of vocabulary and grammatical structures, including some
more complex forms, to describe and narrate with reference to past, present and future
events
There is a recommended vocabulary list for edexcel that I will add below● manipulate the language, using and adapting a variety of structures and vocabulary with
increasing accuracy and fluency for new purposes, including using appropriate style and
register
● make independent, creative and more complex use of the language, as appropriate, to
note down key points, express and justify individual thoughts and points of view, in order
to interest, inform or convince
● translate sentences and short texts from English into the assessed language to convey key
messages accurately and to apply grammatical knowledge of language and structures in
context.
For the grammatical knowledge, I can send you a few docs that summarize things and I'll translate to you what it is saying, and all you need to do is understand For the vocab list, go to page 800 (or 76 on the page) of this link: https://qualifications.pearson.com/content/dam/pdf/GCSE/Arabic/2017/specification-and-sample-assessments/Specification_GCSE_L1-L2_in_Arabic_August_2016_Draft.pdfArabic is a really hard language and us natives struggle a lot with the grammar as well. With that being said, I know you learn better face to face, but if I were you and was left with no choice I would definitely get an online tutor. Practice a lot, write a lot and get constant feedback, this is how I improved my skills and jumped up two grades from 5/7 to a 7/7 (my school follows the IB system). It seems very complex from the bullet points, I wouldn't take any chances remaining with a bad tutor.