Biology a level

I am doing biology A Level (OCR A) and am aiming for an A*. For the first year, I’ve been using 2 textbooks at once but i’m finding that this is too much. Can someone please tell me which textbook is the best to use to get an A* or if I need to continue using 2 textbooks.

What 2 textbook’s are you using?
This one: https://www.whsmith.co.uk/products/a-level-biology-for-ocr-a/ann-fullick/jo-locke/paperback/9780198351924.html?gclid=Cj0KCQjwgNanBhDUARIsAAeIcAsQrWhlVvYYhbX6u6lpbAWS2qg0rRrB1WwOiA5mfHKpl0Gxzy35-yMaAqtAEALw_wcB&gclsrc=aw.ds
And this one: https://www.wob.com/en-gb/books/richard-fosbery/ocr-a-level-biology-student-guide-practical-biology/9781471885617?cq_src=google_ads&cq_cmp=18082217234&cq_con=&cq_med=pla&cq_plac=&cq_net=x&gclid=Cj0KCQjwgNanBhDUARIsAAeIcAubBybkHa3Yq6-lGUJoS_srehZj_cP3uCux23tET_19fvZQIOGWbb0aAt24EALw_wcB#GOR010156250

If so, the top one is for the content (modules 1 to 6, focusing on modules 2 to 5), the bottom one is for module 1 (Practical biology with a lot more detail)

I’m using the top one and this one: https://www.amazon.co.uk/level-Biology-Student-ActiveBook-Science/dp/144799079X/ref=sr_1_4?nodl=1&ie=UTF8&qid=1505662227&sr=8-4&keywords=Biology+ocr+a&dplnkId=9b36b5db-cdd0-44b7-9e66-d26d39300e12

School has given me the bottom one as well but i’m not using it at all. Im scared that I should be using it but i’m still getting A stars without it.

The bottom one is to assist with the practical elements:
The dissections, using a microscope, working scientifically. I used both.
The bottom one is just to reinforce your practical knowledge, use every resource available to you
School gave it you for you to use, not for it to sit untouched at home

Thank you, I understand the bottom book is to reinforce practical elements but is the information already covered in the top book or the other book that I attached above?