I've played Fire Emblem Awakening, Fates, and Three Houses to completion (talk about the replay value on that one). This book will not make the reader take the place of Robin, Corin or Byleth. You will be you, which is what I think would be best here. Nintendo owns all the characters of course, I don't make any claim to the series. You own you and I've only come up with the plots.

Through questionable occurences, you get brought to Fódlan. There you're able to use your nerd knowledge to help its people and maybe woo some cute boys and girls. This follows the story of Fire Emblem three houses if you choose the Golden deer house, so major spoilers for those who have not played it yet. I also don't own Fire Emblem just sayin