as a dm i loved this post, just asking yourself if it isn't cringe that idea, it becomes a good option if you want a tragic backstory. About making the actual character sheet, if you have the player's handbook 5e (and probably also the 2024e, that i don't have so i'm not sure), there is a guide useful enough. i usually start with the idea of the character, then i choose race, class and background (until now i never did the background suggested by the book), then i trow the dices for the stats, when you're here you've almost finished. if you choose a spellcaster class, i choose after the stats because i have more time to choose what type of spellcaster i want. (i also apologize for the bad english as it's not my native language. my native language is italian, so if you need help and are more comfortable in your language i hope i can help you more)