new to web

[Matthew Ngaha]

Hi guys i'm very new to web dev, and getting started with nginx i just
wanted to ask a few things.

Location blocks. Is the idea here to have as many location blocks as
you have web pages? if a location has many files in it will nginx
search if the requested file is in that location? i put a file
"flood.jpg" inside my default root location (below) but i get
permission denied when trying to access the file on my web browser. I
do however see my nginx index homepage. To see "flood.jpg" do i need
to add something to this block?

        location / {
            root   html;
            index  index.html index.htm;
        }

i also made a file in my root html folder: html/test/filename.html

This is also permission denied, but i want to ask. Is it ok accessing
files like this or would it be better to make a specific location
block for them, like:

location /test/filename.html
or
location /test/

should it be INSIDE the root location block: location /
or should it be a separate block?