Like with most light novel/manga to anime adaptions stuff is left out and things are changed. Nothing can be done about it, and it's pretty much expected with anime that get a low production budget. It's sad because a lot of parts I found funny in the source materials, weren't as funny in the anime.
The first episode covers about the first 3 chapters of the light novel (2 chapters of the manga). It skips the most of the prologue, only adding it a bit with how he died and why he's on Seilfall, and a minuscule amount of him exploring his new found abilities. It ends right where chapter 2 of the manga ends, with Ryoma first seeing Eliaria. So for anyone that feels lost or confused about the first episode, I suggest the Web Novel (reboot), Light Novel, or the Manga. Or all three!
The animation isn't the best but it doesn't take away from the story. I have no issue with it, and I think it improved a small bit since I first saw the episode during the Funimation Online Convention.
I expect the anime to cover up to somewhere in volume 2, of the light novel, or for the manga readers up till most of volume 5 of the manga. This is only if they're doing 12-13 episodes (1 cour). If they do 2 cours (24-26 eps), I can see them going all the way up to the end of volume 3 of the light novels, and that part hasn't been put into manga form yet.
The opening theme is where I have most of my issues. The stuff from the opening is in volume 3 of the light novel, and hasn't even been reached in the manga yet. As far as I know this is a 1 cour anime, so about 12-13 episodes long, which means most of the stuff inside the opening theme, we won't get to unless they cut out a lot of stuff and rush the story. If we actually get a 2 cour, anime of 24-26 episodes, then we should see the stuff from the opening. So those who hate spoilers, try to skip the opening if you can. Or just ignore the visuals and just listen to the music.
The ending is just flat out adorable. I can't talk much about those characters because of spoilers so that's all I can say about it. The ending I don't consider spoilery. Unless you have issues seeing characters not yet introduced in the show, this one is safe to watch.