I'm struggling with knowing if I'm using the write rule. Could someone give me advice on this please?

Honestly, I've struggling with these last few sections. So please me understand! I'm begging. Kicking up to the Domain. I knew the guy said to give it time, but that was like 3 sections ago. :(

I'm confused. Could someone explain when is right to make an assumption? and when is it not?

I feel like every time I try to make an assumption I make the wrong ones and I do not know how to fix it.

Please help