Hi, while I did self-study GCSE history I can’t comment on whether it would be possible to do all in one year as I did it in two. But I suppose if you study with the right technique and study high-yield topics it might be possible.
I would recommend for general history tips:
. Not sure which exam board you do but I found Hodder and Pearson Revise textbooks useful and they contained model answers too as well as plenty of source evaluation practice
. if you find flashcards useful for remembering dates and important events then you can try. I did make them for remembering events in the Cold War and in Weimar Germany and included key info points in the back of each flashcards. Making your own for history is much better than buying or using other flashcards in my opinion.
. BBC Bitesize/BBC Teach have some good videos for some history topics. For others BBC documentaries/Youtube can be helpful