You have to create labels for that. A label in Gmail is a folder for arranging your mails. After moving them to labels, they don't show up in Inbox.
A sub folder is when you put a folder in another folder and a sub level folder is when you put more than one sub folder in another sub folder.....
This folder is called the Inbox, and contains both read and unread messages, which can be sorted to various sub-folders.
There are a number of ways. Probably the simplest is to open a folder window (My Computer or Windows Explorer) for the folder in which you want to create a sub-folder. Right click in a blank area of the file list pane, and move the mouse to New. Select Folder in the sub-menu. A sub-folder called New Folder, with the name highlighted (selected), will be created. Type the name you want for your sub-folder, then press Enter. This will replace New Folder as the name of the sub-folder.
How do you copy a folder of many files from my computer into inbox of my email?
Inbox
You can make about 5 sub-sub folders in another folder.
Inbox
The sub folder is a folder inside the file folder. For example... The "Sample Pictures" folder is a sub folder to the "My Pictures" folder. It's pretty straight forward and simple...so hope that helps?
sub folder.
gowing on the inbox. .
Inbox is a folder, where you receive mails from different people. if you don't get the mail in inbox, it goes to junk or spam tab.