for the first one, you can find the dagger just right under the grass out of the house, its pretty visible so you mustve found it by now.
for the third one, you can just bring ingredients to Janet for her to cook food for you, there is no need to talk to her. Though I don't know which specific one is the right food cuz I just made them all.
and for the fourth one theres ancient roots (right next to the dwarf statue) in the melkors tomb, you just need a empty bottle to take it.
I don't know what you should do for the third one yet I didn't proceed on the church storyline yet but if I do so I'll update and tell it.