hii! Here are a few youtube channels and websites that can help:
English Literature and Language: mr salles teaches english, mr everything english, stacey reay.
Maths: mathsgenie (website and videos on youtube), thegcsemathstutor, and corbett maths.
Triple Science: freesciencelessons, cognito, bbc bitesize.
Business: bizconsesh, bbc bitesize.
I don't do history so I'm not sure what websites or videos that will help?
Also there's youtube channel called smile with sola, she gives advice on how to get grade 9's on all the subjects!!
Do past papers (you can find the past papers from the examboards or other webites that may have past papers)
I hope you find this a bit more useful.
Good luck on your Y10 mock exams!!!!