I'm not that far into the game myself, but I'm also playing on hard mode, and I'm sure it's going to get tough at some point, but if you're referring to the tutorial at the beginning, then I didn't have that problem. It seemed like the game guided me on every turn telling me where to go. It sounds like you might be farther than me, though.
Are you doing classic as well? That's how I played through Conquest, and I remember some missions requiring multiple resets, but I eventually managed, so I figured I'd carry on that legacy with Three Houses as well.
Not the tutorial level where you have all three house leaders. It's the second time you are fighting the bandit leader though. When you kill this guy...
Playing on classic mode. So if a single unit dies you have to rewind time.
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