How to Create A New Document in Illustrator, with Video Tutorial .

Create a new document .

A document is the space in which you create artwork. You start a new document by choosing a new document profile based on your intended output.Each profile includes preset values for size, color mode, units, orientation, transparency, and resolution.All use one artboard, by default.

Documents profiles:

 Welcome screen

• Print Document.
• Web Document.
• Mobile And Devices Document .
• Video And Film Document .
• Basic CMYK Document .
• Basic RGB Document .

 Create a new document from the Welcome screen, or by using File > New . 

1. Type a name for your document. 
2. Specify the number of artboards for your document, and their order .
3. Specify the default both horizontal and vertical spacing between artboards. 
4. Specify the default size, units of measure, and layout for all artboards.
5. Specify the position of the bleed along each side of the artboard. 

Note: You can change these settings after you create the document by choosing File > Document Setup and specifying new settings .

Create a new document from a template .

1  Do one of the following:
   •Choose File > New From Template.
   •Choose File > New. In the New Document dialog box, click Templates.
   •In the Welcome screen, click From Template in the Create New list.
2  In the New From Template dialog box, locate and select a template, and click New.

Illustrator diagram .

that is the illustrator interface and look to help understanding the explanation that I am giving.

• It shows the menu bar.
• The options bar.
• Tabbed Document windows.To move from document to another.
• The Tools panel that contains tools for creating and editing images, artwork, page elements, and more.
•  The control panel  (The option bar) displays options for the currently selected tool .
• The Document window shows the file you are working on.
• The status bar  at the lower-left edge of the illustration window. 

I hope it is useful.

Thanks
Manal Raafat