Latest Pilot Jobs is what i used
I got almost full marks according to my feedback (dont know how haha) essentially I did the practice tests on all difficulties and when i didn't know it I went to BBC bitesize and learnt from the bottom. Also I didn't know any of it when I started so its definitely doable, I did about 2 hours a day for a couple of months.
They have interview tips and stuff as well which was pretty on point with what I have used as both an interviewer and interviewee during my life.