for example, i'm at the church and i got this tip that a random guy was missing. how do i take that mission? or do i just have to look around hoping i might find him? do i have to talk to someone for a lead?

also...

in the first part at the cabin there was a hurt girl. and it seemed like i needed to find medicine for her which i had a couple of painkillers and stuff, but i couldnt hand them to her, and after a while she died or something... was it my fault? how was i supposed to give her the medicine?