Hydro beginner tips

A question from a fellow grower:

This is my first time ever using hydro to grow I have always did my growing outside in good old dirt
I’m worried about not getting what I should out of my plants I don’t know what needs to be put in the water and I don’t understand how to just grow roots in some kind of rock
I have 5 White Widow female seeds in route to me and since I have no idea what to do I don’t want to lose the seeds cause I don’t know what to do
The reason I am growing in a grow box now cause I am paralyzed from the chest down and I don’t want anyone knowing my business so I am not going to ask anyone that I do know that knows about it any help with this would be very helpful thanks for your time with my problem and sorry for wasting your time with me on this but I really need the help my friend