Is this realistic? (IGCSE self-study)

Hi, I'm planning on taking the May/June 26 but I had just started the syllabus..
Is it possible to finish it in a year?
Not only that, my parents refuse to enroll me in a school and wants me to do both the national curriculum and IGCSE..
I have to go to the school for the other curriculum so my times are mostly wasted. I do not have any tutors either.
Important note: I'm not going to an university in my country and my country's certificate is rarely accepted. My parents purely wants me to do it because that's what they did. They also wants me to continue self-studying for A-levels idk if that's doable too.
I'm currently taking 5 subjects, is that too little? I don't really have time for a lot of subjects so I plan to take a few more later on if I really need it.
I don't really know what I want to do yet so this is a mix of subjects... I'm interested in humanities but honestly, I don't think that I'll actually go into it.
English Language A
Mathematics B
Physics
Business
Computer Science
(Edexcel exam board)
Is it alright for me to take only one science? If my interests change can I take other ones in A-levels or would it be hard for me to follow as I have no basics (maybe the ones from the national curriculum might help)
Also English Language A, I need to get feedback for some of the texts
But I don't have any tutors..
Is it okay if I just look at marking schemes and maybe use chatgpt (yes I know that it's bad but I'm quite desperate)
I talked to a tutor online
They told me that English Language A tutors are rare and I don't really need it
Also that, I should switch to English Language B instead
There's abundance of resources and online tutors out there (most schools don't teach it either, the only one I found was out of state)
And it's hard for students to achieve good grades in Lang A so there would be complications when applying to universities and colleges later on
Here's the thing, I prefer Lang A over B
I don't wish to switch at all
Sure it's quite complicated with analysis and all but maybe if I study really hard I might be able to do it
I don't know anymore
Am I being too unrealistic?
Please share some advice
Thank you!!

First of all - The Student Room is a great place to receive support - you might want to set up a grow your grades blog in September or even begin now https://www.thestudentroom.co.uk/forumdisplay.php?f=1659
I would look at the course content for all subjects you're interested in + past exam papers and marking schemes.
If you're already thinking about A-levels it might be worth exploring what you might like to study and which GCSEs would set you up for those.
If you're focusing on only five subjects it could be posssible within the year. However, most courses are two years in length (also due to time taken out for school holidays). Is there a reason when you wish to complete in a year?