Help! First time as a DM, teaching newbies, and all over webcams.

Hi,

I'm fairly experienced in playing RPGs but I have never DM'd a game before. My family is locked down in quarantine spread amongst three separate timezones and my mom & brothers want to learn Pathfinder.

Mom is an avid reader, her favorite book series in high school was LOTR. She's also on the opposite end of the continent, so no physical sharing of books/sheets.

Two of my brothers have played Pathfinder before, one of them is more experienced than I am.

The last brother is dyslexic but lives close enough that I can drop off a character sheet/papers if necessary. Due to the current state of things in the US I would do that while he's out, no working on stuff in the same room.

I was hoping to do just a basic level 1 adventure on the water with some Greek mythology thrown in.

Any advice on where to start? We have class/race picked for everyone but I'm not sure how many decisions I should make for the newbies and how much I should just cut them loose.

Any open source books you would recommend that I can distribute to people?

Trying to keep it simple and manageable over a webcam/chat.

Thanks!