So, you are possibly either a phasmophobe or just got the game, or maybe you're both. As a person who has played the game for over 30 hours, I can be of assist to those who are too afraid to step foot into even the tutorial house.

There are multiple types of ghosts in the game. What they are can determine their ability, activity, and what they are able to do.
These ghosts range from:

Demon,
Revenant,
Jinn,
Oni,
Poltergeist,
Spirit,
Banshee,
Wraith,
Yurei,
Mare,
Shade,
and Phantom

With each of them being unique, it can take time to remember who can do what.

Now, you might be wondering, "How does this help me to know when I could possibly die?"
You can die, but there is a catch. The ghost CANNOT hurt you unless it begins hunting. Hunting is when the ghost emerges and begins searching for someone to kill. You will know it starts from your light/other's lights flashing on and off, room lights flashing, and radio static. The ghost is close when you can hear your heartbeat. Your best options are to either hide, or run if you feel speedy enough. Make sure you aren't facing a Revenant however, as you are basically a slug against a cheetah.

Hiding spots can range from hiding in the corner of the room with you lights off, closets, or just anywhere the ghost cannot see you. Your voice doesnt matter, however having your flashlight off does, as it may show you or other players.

Luckily, in amateur difficulty, you have 5 minutes before it can actually hurt you

Intermediate is 2 mins

and Professional has no timer.

So remember, if your flashlight begins turning off and on
Run and hide, ASAP.

This was my first guide, so I apologize for the low quality, but hopefully you can learn something from it. I'd appreciate any feedback, and feel free to message me about questions. Take care and safe ghost hunting!