I've also done IGCSEs
For english-Mr everythingthing English
For math- GCSE this tutor
These are the YouTubers I watched to get good grades in eng and math. Go on the playlists of their channel and revise off their vids. I only got a book and few pens to revise and study. You don't need any other study tools, textbooks, tutors. trust me (accept basic math tools). I paid over £1000 for a course online that did absolutely nothing for me so I decided to use YouTube and luckily it was one of the best decisions Ive ever made. BTW for reference I hadn't gone to school in 2years and the last grade I got in school was a 2 in eng and prob 3/4 in math. For my GCSEs I got 8s by revising just one month before(but make sure u don't do this and revise consistently through out the year as it's mentally exhausting). I know u can do it. Best of luck. Hope this helps.