Restful API design Help - 3NF Database - JWT

I am about to develop a restful api for my web app, before i begin development,i have few confusion regarding designing the restful api.

1) I have a user table that can create an Item but that item has location, type and image table attached to it. I want to make a post request to the item table in such a way that i can fill item, location, type and images table all in one go. What will be the best design approach to do that? Do i need to do it separately or can the person who use my api can fill all this data in one api call. I tried this using form, where i save all this data into there particular table and then later link them with there ID.

2) Is restful api good for database that is in 3NF state?

3) Is JWT good enough for restful api security ? I dont want to use Oauth2.

i will be using laravel 5.3 for developing the restful api.

via Chebli Mohamed