PLEASE, PLEASE, PLEASE learn the difference between ‘rein’ and ‘reign’!
I know, everyone has mistakes that really get under their skin, and this one is probably mine. I can’t even count the number of stories I’ve read where riders pull on the ‘reigns’ of their horses, while Kings ‘rein’ over their people. (I suppose it is something that those writers at least seem to realize neither one is spelled ‘rain’…)
If these words, or any others, give you problems, LOOK THEM UP. Make lists of words you commonly misspell or confuse, and REFER to the list whenever you use those words. I do that for further/farther and lay/lie. You can do it too. Don’t slap someone out of the story you are weaving by allowing junk mistakes to creep in. You want the reader totally immersed in your tale, from beginning to end.
Spellcheck is nice, but using the wrong word though spelled correctly won’t cause it to alert you. Grammar check probably won’t catch it either if you use the wrong word. You are on your own for your word choice.
Details like that can make a difference. Besides, you want to end my misery, don’t you?
Addendum: If you want to see the parts of a horse labeled with their correct name, here is a place you can start: https://www.merriam-webster.com/art/med/horse.htm
Or you can Google for more.