I feel like I have the right reasonings, but I don't do things the exact what that the video or the answer shows. For instance in question one, he says you can shorten the sufficient conditions and exclude "newly arrived" but he doesn't show how the process for that circumstance. Does anyone relate?

is there a way to find more practice for these types of questions?

Do sufficient and necessary conditions relate to using an active or passive voice? For instance the subject being acted upon, or if the subject receives the action.