I'm sorry you feel that way about the plot and game! Unfortunately, this is not a stat heavy IF, but s more narrative IF so you're making choices but following the same script. I dislike stat heavy IF games and prefer allowing players to choose whatever choices they want without being locked from choosing something simply because of earlier choices.
As for Ahlf not training the MC, this was answered on my Tumblr. Ahlf hated his military background and didn't want to return to that by teaching the MC how to fight - he also had a hard time with the MC in general being their child. It's a complicated family relationship that creates a lot of turmoil for him as a character.
Have you reached Part of the game? There's something called divine blessings and you can unlock that skill later on.
That said, if this isn't to your liking, that's completely fine. I know that the game won't be for some and you giving it a try is enough 😊